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The present work delves into the enigmatic world of mitochondrial alpha-keto acid dehydrogenase complexes discussing their metabolic significance, enzymatic operation, moonlighting activities, and pathological relevance with links to underlying structural features. This ubiquitous family of related but diverse multienzyme complexes is involved in carbohydrate metabolism (pyruvate dehydrogenase complex), the citric acid cycle (α-ketoglutarate dehydrogenase complex), and amino acid catabolism (branched-chain α-keto acid dehydrogenase complex, α-ketoadipate dehydrogenase complex); the complexes all function at strategic points and also participate in regulation in these metabolic pathways. These systems are among the largest multienzyme complexes with at times more than 100 protein chains and weights ranging up to ~10 million Daltons. Our chapter offers a wealth of up-to-date information on these multienzyme complexes for a comprehensive understanding of their significance in health and disease.
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Mitocondrias , Humanos , Mitocondrias/metabolismo , Mitocondrias/enzimología , Animales , Ciclo del Ácido Cítrico/fisiología , Complejo Cetoglutarato Deshidrogenasa/metabolismo , Complejo Cetoglutarato Deshidrogenasa/químicaRESUMEN
Clinically relevant disease-causing variants of the human dihydrolipoamide dehydrogenase (hLADH, hE3), a common component of the mitochondrial α-keto acid dehydrogenase complexes, were characterized using a multipronged approach to unravel the molecular pathomechanisms that underlie hLADH deficiency. The G101del and M326V substitutions both reduced the protein stability and triggered the disassembly of the functional/obligate hLADH homodimer and significant FAD losses, which altogether eventually manifested in a virtually undetectable catalytic activity in both cases. The I12T-hLADH variant proved also to be quite unstable, but managed to retain the dimeric enzyme form; the LADH activity, both in the forward and reverse catalytic directions and the affinity for the prosthetic group FAD were both significantly compromised. None of the above three variants lent themselves to an in-depth structural analysis via X-ray crystallography due to inherent protein instability. Crystal structures at 2.89 and 2.44 Å resolutions were determined for the I318T- and I358T-hLADH variants, respectively; structure analysis revealed minor conformational perturbations, which correlated well with the residual LADH activities, in both cases. For the dimer interface variants G426E-, I445M-, and R447G-hLADH, enzyme activities and FAD loss were determined and compared against the previously published structural data.
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Dihidrolipoamida Deshidrogenasa , Humanos , Dihidrolipoamida Deshidrogenasa/genética , Conformación Proteica , 3-Metil-2-Oxobutanoato Deshidrogenasa (Lipoamida)RESUMEN
Colorectal cancer (CRC) has one of the highest incidences among all types of malignant diseases, affecting millions of people worldwide. It shows slow progression, making it preventable. However, this is not the case due to shortcomings in its diagnostic and management procedure and a lack of effective non-invasive biomarkers for screening. Here, we discuss CRC-associated microRNAs (miRNAs) and gut microbial species with potential as CRC diagnostic and therapy biomarkers. We provide rich evidence of cross-kingdom miRNA-mediated interactions between the host and gut microbiome. miRNAs have emerged with the ability to shape the composition and dynamics of gut microbiota. Intestinal microbes can uptake miRNAs, which in turn influence microbial growth and provide the ability to regulate the abundance of various microbial species. In the context of CRC, targeting miRNAs could aid in manipulating the balance of the microbiota. Our findings suggest the need for correlation analysis between the composition of the gut microbiome and the miRNA expression profile.
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Neoplasias Colorrectales , Microbioma Gastrointestinal , MicroARNs , Microbiota , Humanos , Microbioma Gastrointestinal/genética , MicroARNs/genética , Neoplasias Colorrectales/diagnóstico , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/terapia , BiomarcadoresRESUMEN
Glioblastoma is the most common malignant tumor of the central nervous system (CNS) in adults. Glioblastoma cells show increased glucose consumption associated with poor prognosis. Since mitochondria play a crucial role in energy metabolism, mutations and copy number changes of mitochondrial DNA may serve as biomarkers. As the brain is difficult to access, analysis of mitochondria directly from the brain tissue represents a challenge. Exosome analysis is an alternative (still poorly explored) approach to investigate molecular changes in CNS tumors. We analyzed brain tissue DNA and plasma-derived exosomal DNA (exoDNA) of 44 glioblastoma patients and 40 control individuals. Quantitative real-time PCR was performed to determine mtDNA copy numbers and the Kruskal-Wallis and Mann-Whitney U test were used for statistical analysis of data. Subsequently, sequencing libraries were prepared and sequenced on the MiSeq platform to identify mtDNA point mutations. Tissue mtDNA copy number was different among controls and patients in multiple comparisons. A similar tendency was detected in exosomes. Based on NGS analysis, several mtDNA point mutations showed slightly different frequencies between cases and controls, but the clinical relevance of these observations is difficult to assess and likely less than that of overall mtDNA copy number changes. Allele frequencies of variants were used to determine the level of heteroplasmy (found to be higher in exo-mtDNA of control individuals). Despite the suggested potential, the use of such biomarkers for the screening and/or diagnosis of glioblastomas is still limited, thus further studies are needed.
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Exosomas , Glioblastoma , Adulto , Humanos , Variaciones en el Número de Copia de ADN/genética , Glioblastoma/genética , Heteroplasmia , Exosomas/genética , ADN Mitocondrial/genética , ADN Mitocondrial/análisis , Mitocondrias/genética , Mutación/genética , EncéfaloRESUMEN
Lynch syndrome (LS) is an autosomal dominant inherited cancer predisposition disorder, which may manifest as colorectal cancer (CRC), endometrial cancer (EC) or other malignancies of the gastrointestinal and genitourinary tract as well as the skin and brain. Its genetic cause is a defect in one of the four key DNA mismatch repair (MMR) loci. Testing of patients at risk is currently based on the absence of MMR protein staining and detection of mutations in cancer tissue and the germline, microsatellite instability (MSI) and the hypermethylated state of the MLH1 promoter. If LS is shown to have caused CRC, lifetime follow-up with regular screening (most importantly, colonoscopy) is required. In recent years, DNA and RNA markers extracted from liquid biopsies have found some use in the clinical diagnosis of LS. They have the potential to greatly enhance the efficiency of the follow-up process by making it minimally invasive, reproducible, and time effective. Here, we review markers reported in the literature and their current clinical applications, and we comment on possible future directions.
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Neoplasias Colorrectales Hereditarias sin Poliposis , Neoplasias Endometriales , Ácidos Nucleicos , Biomarcadores , Biomarcadores de Tumor/análisis , Biomarcadores de Tumor/genética , Neoplasias Colorrectales Hereditarias sin Poliposis/diagnóstico , Neoplasias Colorrectales Hereditarias sin Poliposis/genética , Neoplasias Colorrectales Hereditarias sin Poliposis/patología , Reparación de la Incompatibilidad de ADN/genética , Neoplasias Endometriales/genética , Femenino , Mutación de Línea Germinal , Humanos , Biopsia Líquida , Inestabilidad de MicrosatélitesRESUMEN
The human 2-oxoadipate dehydrogenase complex (OADHc) in L-lysine catabolism is involved in the oxidative decarboxylation of 2-oxoadipate (OA) to glutaryl-CoA and NADH (+H+). Genetic findings have linked the DHTKD1 encoding 2-oxoadipate dehydrogenase (E1a), the first component of the OADHc, to pathogenesis of AMOXAD, eosinophilic esophagitis (EoE), and several neurodegenerative diseases. A multipronged approach, including circular dichroism spectroscopy, Fourier Transform Mass Spectrometry, and computational approaches, was applied to provide novel insight into the mechanism and functional versatility of the OADHc. The results demonstrate that E1a oxidizes a non-cognate substrate 2-oxopimelate (OP) as well as OA through the decarboxylation step, but the OADHc was 100-times less effective in reactions producing adipoyl-CoA and NADH from the dihydrolipoamide succinyltransferase (E2o) and dihydrolipoamide dehydrogenase (E3). The results revealed that the E2o is capable of producing succinyl-CoA, glutaryl-CoA, and adipoyl-CoA. The important conclusions are the identification of: (i) the functional promiscuity of E1a and (ii) the ability of the E2o to form acyl-CoA products derived from homologous 2-oxo acids with five, six, and even seven carbon atoms. The findings add to our understanding of both the OADHc function in the L-lysine degradative pathway and of the molecular mechanisms leading to the pathogenesis associated with DHTKD1 variants.
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Errores Innatos del Metabolismo de los Aminoácidos , Complejo Cetoglutarato Deshidrogenasa , Errores Innatos del Metabolismo de los Aminoácidos/metabolismo , Humanos , Complejo Cetoglutarato Deshidrogenasa/metabolismo , Lisina/metabolismo , NAD/metabolismo , Oxidación-ReducciónRESUMEN
2-Oxoadipate dehydrogenase (E1a, also known as DHTKD1, dehydrogenase E1, and transketolase domain-containing protein 1) is a thiamin diphosphate-dependent enzyme and part of the 2-oxoadipate dehydrogenase complex (OADHc) in l-lysine catabolism. Genetic findings have linked mutations in the DHTKD1 gene to several metabolic disorders. These include α-aminoadipic and α-ketoadipic aciduria (AMOXAD), a rare disorder of l-lysine, l-hydroxylysine, and l-tryptophan catabolism, associated with clinical presentations such as developmental delay, mild-to-severe intellectual disability, ataxia, epilepsy, and behavioral disorders that cannot currently be managed by available treatments. A heterozygous missense mutation, c.2185GâA (p.G729R), in DHTKD1 has been identified in most AMOXAD cases. Here, we report that the G729R E1a variant when assembled into OADHc in vitro displays a 50-fold decrease in catalytic efficiency for NADH production and a significantly reduced rate of glutaryl-CoA production by dihydrolipoamide succinyl-transferase (E2o). However, the G729R E1a substitution did not affect any of the three side-reactions associated solely with G729R E1a, prompting us to determine the structure-function effects of this mutation. A multipronged systematic analysis of the reaction rates in the OADHc pathway, supplemented with results from chemical cross-linking and hydrogen-deuterium exchange MS, revealed that the c.2185GâA DHTKD1 mutation affects E1a-E2o assembly, leading to impaired channeling of OADHc intermediates. Cross-linking between the C-terminal region of both E1a and G729R E1a with the E2o lipoyl and core domains suggested that correct positioning of the C-terminal E1a region is essential for the intermediate channeling. These findings may inform the development of interventions to counter the effects of pathogenic DHTKD1 mutations.
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Variación Genética , Cetona Oxidorreductasas/química , Cetona Oxidorreductasas/metabolismo , Lisina/metabolismo , Fibroblastos/química , Fibroblastos/metabolismo , Variación Genética/genética , Humanos , Complejo Cetoglutarato Deshidrogenasa , Cetona Oxidorreductasas/genética , Cinética , Lisina/química , Modelos Moleculares , Estructura Molecular , Relación Estructura-ActividadRESUMEN
Human dihydrolipoamide dehydrogenase (hLADH, hE3) deficiency (OMIM# 246900) is an often prematurely lethal genetic disease usually caused by inactive or partially inactive hE3 variants. Here we report the crystal structure of wild-type hE3 at an unprecedented high resolution of 1.75 Å and the structures of six disease-causing hE3 variants at resolutions ranging from 1.44 to 2.34 Å. P453L proved to be the most deleterious substitution in structure as aberrations extensively compromised the active site. The most prevalent G194C-hE3 variant primarily exhibited structural alterations close to the substitution site, whereas the nearby cofactor-binding residues were left unperturbed. The G426E substitution mainly interfered with the local charge distribution introducing dynamics to the substitution site in the dimer interface; G194C and G426E both led to minor structural changes. The R460G, R447G and I445M substitutions all perturbed a solvent accessible channel, the so-called H+/H2O channel, leading to the active site. Molecular pathomechanisms of enhanced reactive oxygen species (ROS) generation and impaired binding to multienzyme complexes were also addressed according to the structural data for the relevant mutations. In summary, we present here for the first time a comprehensive study that links three-dimensional structures of disease-causing hE3 variants to residual hLADH activities, altered capacities for ROS generation, compromised affinities for multienzyme complexes and eventually clinical symptoms. Our results may serve as useful starting points for future therapeutic intervention approaches.
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Dihidrolipoamida Deshidrogenasa/deficiencia , Complejos Multienzimáticos/metabolismo , Dominio Catalítico , Dihidrolipoamida Deshidrogenasa/genética , Humanos , Complejos Multienzimáticos/genética , Mutagénesis Sitio-Dirigida , Mutación/genética , Conformación Proteica , Especies Reactivas de Oxígeno/metabolismoRESUMEN
BACKGROUND Wilms' tumor is a common renal malignancy of early childhood with a generally favorable prognosis depending upon histological subtype. It is becoming increasingly clear that differences in miRNA (microRNA) expression signature represent important clues helping us predict a tumor's response to chemotherapy. In our study, we aimed to reveal miRNAs deregulated in regressive Wilms' tumors from FFPE (formalin-fixed, paraffin-embedded) samples, also showing whether such samples are reliable miRNA sources in Wilms' tumor. MATERIAL AND METHODS Samples from 8 Hungarian patients (3 males, 5 females, aged 1 to 7 years) were analyzed by qRT-PCR (quantitative real-time PCR). A PCR array was used in a pilot experiment, and selected miRNAs (miR-128-3p, miR-184, miR-194-5p, miR-203a) were studied in the rest of the samples using individual primers. RESULTS miR-194-5p was underexpressed in all tumor samples. miR-184 and miR-203a were underexpressed in 7 cases, the exception being a case with a high ratio of necrotic blastemal tissue. Results obtained with miR-128-3p are difficult to interpret due to varying directions of expression changes. CONCLUSIONS We conclude that a downregulation of miR-184, miR-194-5p, and miR-203a expression is observed in both regressive and blastemal tumors, but larger-scale studies are needed to confirm whether the degree of their underexpression correlates with the number of blastemal elements in a sample. In most of our FFPE samples aged up to 9 years, RNA extraction provided miRNA with quantity and quality sufficient for qRT-PCR-based analysis, emphasizing the relevance of pathological archives as miRNA sources in future studies.
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Perfilación de la Expresión Génica/métodos , Neoplasias Renales/genética , MicroARNs/genética , Adhesión en Parafina/métodos , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Tumor de Wilms/genética , Niño , Preescolar , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Hungría , Lactante , MasculinoRESUMEN
OBJECTIVES: Perioperative stress affects the outcome of carotid endarterectomy performed under regional anesthesia. Here we aimed to explore the temporal profile of the stress marker cortisol and its relationship to high-sensitivity troponin-T, matrix metalloproteinase-9, tissue inhibitor of metalloproteinase-1, and S100B as an indicator of blood-brain barrier alteration in the systemic circulation. METHODS: Prospective part of the study: a total of 31 patients with significant carotid stenosis scheduled for carotid endarterectomy in regional anesthesia were enrolled. Follow-up part of the study and retrospective analysis of the outcome: each patient was followed up to five years and morbidity as well as mortality data were collected from an electronic database. Blood samples from each patient were serially taken; prior to surgery (T1), at the time of reperfusion (T2), 24 h (T3) and 72 h later postoperatively (T4), then the plasma concentration of each biomarker was measured. Besides, the clinical and surgical factors and perioperative adverse events were recorded. RESULTS: More positive correlations were found between: the early change of S100B (T2-T1) and late change in plasma cortisol level (T4-T3) (r = 0.403; p < 0.05); the early change of cortisol (T2-T1) and the early postoperative change of plasma matrix metalloproteinase-9 level (T3-T2) (r = 0.432; p = 0.01); the plasma concentration of tissue inhibitor of metalloproteinase-1 at 24 postoperative hours and the late change in plasma high-sensitivity troponin-T level (T4-T3) (r = 0.705; p < 0.001). Five patients needed an intraoperative shunt in whom the high-sensitivity troponin-T was elevated even prior to surgery, but definitive stroke never occurred. Plasma matrix metalloproteinase-9 concentration at reperfusion independently predicted the five-year mortality with a cut-off value of 456 ng/ml (sensitivity: 86%, specificity: 84%, area 0.887, p = 0.002). CONCLUSIONS: A higher intraoperative change in S100B level reflecting carotid endarterectomy induced acute silent brain ischemia was associated with more pronounced post-operative change of cortisol. An early elevation of cortisol was found to be associated with a delayed increase of matrix metalloproteinase-9. Importantly, an increased high-sensitivity troponin-T even prior to carotid endarterectomy may predict clamp intolerance, and elevated matrix metalloproteinase-9 at reperfusion suggests a poor outcome.
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Estenosis Carotídea/cirugía , Endarterectomía Carotidea/efectos adversos , Troponina T/sangre , Anciano , Anestesia de Conducción/efectos adversos , Biomarcadores/sangre , Estenosis Carotídea/sangre , Estenosis Carotídea/diagnóstico por imagen , Femenino , Humanos , Hidrocortisona/sangre , Masculino , Metaloproteinasa 9 de la Matriz/sangre , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Estudios Prospectivos , Subunidad beta de la Proteína de Unión al Calcio S100/sangre , Factores de Tiempo , Inhibidor Tisular de Metaloproteinasa-1/sangre , Resultado del Tratamiento , Regulación hacia ArribaRESUMEN
AIM: To compare the effect of adjunctive lidocaine-based scalp block and laryngotracheal local anesthesia vs general anesthesia only on pro-inflammatory cytokine concentrations in patients with non-ruptured brain aneurysms undergoing elective open surgery. METHODS: This parallel, randomized, controlled, open-label trial was conducted at Clinical Hospital Center Zagreb between March 2019 and March 2020. At the beginning of anesthesia, lidocaine group received 40 mg of 2% lidocaine for laryngotracheal topical anesthesia and 4 mg/kg for the scalp block. Control group underwent general anesthesia only. Plasma concentrations of IL-6, TNF-α, and IL-1ß were measured before anesthesia (S0); at the incision (S1); at the end of surgery (S2); 24 hours postoperatively (S3). Cerebrospinal fluid (CSF) cytokine concentrations were measured at the incision (L1) and the end of surgery (L2). RESULTS: Forty patients (each group, 20) were randomized; 37 were left in the final analysis. IL-6 plasma concentrations increased significantly compared with baseline at S3 in lidocaine group, and at S2 and S3 in control group. In both groups, changes in TNF-α and IL-1ß were not significant. CSF cytokine concentrations in lidocaine group did not change significantly; in control group IL-6 and IL-1ß were significantly higher at L2 than at L1. CSF IL-6 in control group significantly increased at L2, but TNF-α and IL-1ß did not. No differences in clinical outcome and complication rates were observed. CONCLUSION: Adjunctive lidocaine-based scalp block and laryngotracheal local anesthesia might attenuate CSF IL-6 concentration increase in patients with brain aneurysm.
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Aneurisma Intracraneal , Anestesia General , Anestesia Local , Anestésicos Locales , Citocinas , Humanos , Aneurisma Intracraneal/tratamiento farmacológico , Aneurisma Intracraneal/cirugía , Lidocaína , Cuero CabelludoRESUMEN
(1) Background: Glioblastoma multiforme (GBM) is among the most aggressive cancers with a poor prognosis. Treatment options are limited, clinicians lack efficient prognostic and predictive markers. Circulating miRNAs-besides being important regulators of cancer development-may have potential as diagnostic biomarkers of GBM. (2) Methods: In this study, profiling of 798 human miRNAs was performed on blood plasma samples from 6 healthy individuals and 6 patients with GBM, using a NanoString nCounter Analysis System. To validate our results, five miRNAs (hsa-miR-433-3p, hsa-miR-362-3p, hsa-miR-195-5p, hsa-miR-133a-3p, and hsa-miR-29a-3p) were randomly chosen for RT-qPCR detection. (3) Results: In all, 53 miRNAs were significantly differentially expressed in plasma samples of GBM patients when data were filtered for FC 1 and FDR 0.1. Target genes of the top 39 differentially expressed miRNAs were identified, and we carried out functional annotation and pathway enrichment analysis of target genes via GO and KEGG-based tools. General and cortex-specific protein-protein interaction networks were constructed from the target genes of top miRNAs to assess their functional connections. (4) Conclusions: We demonstrated that plasma microRNA profiles are promising diagnostic and prognostic molecular biomarkers that may find an actual application in the clinical practice of GBM, although more studies are needed to validate our results.
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Biomarcadores de Tumor/genética , MicroARN Circulante/genética , Redes Reguladoras de Genes , Glioblastoma/genética , Glioblastoma/patología , Biomarcadores de Tumor/metabolismo , Estudios de Casos y Controles , MicroARN Circulante/metabolismo , Biología Computacional , Perfilación de la Expresión Génica , Glioblastoma/sangre , Humanos , Pronóstico , Mapas de Interacción de ProteínasRESUMEN
Early detection, characterization and monitoring of cancer are possible by using extracellular vesicles (EVs) isolated from non-invasively obtained liquid biopsy samples. They play a role in intercellular communication contributing to cell growth, differentiation and survival, thereby affecting the formation of tumor microenvironments and causing metastases. EVs were discovered more than seventy years ago. They have been tested recently as tools of drug delivery to treat cancer. Here we give a brief review on extracellular vesicles, exosomes, microvesicles and apoptotic bodies. Exosomes play an important role by carrying extracellular nucleic acids (DNA, RNA) in cell-to-cell communication causing tumor and metastasis development. We discuss the role of extracellular vesicles in the pathogenesis of cancer and their practical application in the early diagnosis, follow up, and next-generation treatment of cancer patients.
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Exosomas/genética , Exosomas/metabolismo , Neoplasias/patología , Biomarcadores de Tumor , Comunicación Celular , Progresión de la Enfermedad , Detección Precoz del Cáncer , Exosomas/patología , Humanos , Neoplasias/tratamiento farmacológico , Neoplasias/genética , Neoplasias/metabolismo , Medicina de Precisión , Microambiente TumoralRESUMEN
MOTIVATION: Non-invasive prenatal testing or NIPT is currently among the top researched topic in obstetric care. While the performance of the current state-of-the-art NIPT solutions achieve high sensitivity and specificity, they still struggle with a considerable number of samples that cannot be concluded with certainty. Such uninformative results are often subject to repeated blood sampling and re-analysis, usually after two weeks, and this period may cause a stress to the future mothers as well as increase the overall cost of the test. RESULTS: We propose a supplementary method to traditional z-scores to reduce the number of such uninformative calls. The method is based on a novel analysis of the length profile of circulating cell free DNA which compares the change in such profiles when random-based and length-based elimination of some fragments is performed. The proposed method is not as accurate as the standard z-score; however, our results suggest that combination of these two independent methods correctly resolves a substantial portion of healthy samples with an uninformative result. Additionally, we discuss how the proposed method can be used to identify maternal aberrations, thus reducing the risk of false positive and false negative calls. AVAILABILITY AND IMPLEMENTATION: The open-source code of the proposed methods, together with test data, is freely available for non-commercial users at github web page https://github.com/jbudis/lambda. SUPPLEMENTARY INFORMATION: Supplementary materials are available at Bioinformatics online.
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Diagnóstico Prenatal , Femenino , Humanos , Embarazo , Sensibilidad y EspecificidadRESUMEN
In the developing and adult brain, oligodendrocyte precursor cells (OPCs) are influenced by neuronal activity: they are involved in synaptic signaling with neurons, and their proliferation and differentiation into myelinating glia can be altered by transient changes in neuronal firing. An important question that has been unanswered is whether OPCs can discriminate different patterns of neuronal activity and respond to them in a distinct way. Here, we demonstrate in brain slices that the pattern of neuronal activity determines the functional changes triggered at synapses between axons and OPCs. Furthermore, we show that stimulation of the corpus callosum at different frequencies in vivo affects proliferation and differentiation of OPCs in a dissimilar way. Our findings suggest that neurons do not influence OPCs in "all-or-none" fashion but use their firing pattern to tune the response and behavior of these nonneuronal cells.
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Células Madre Adultas/fisiología , Cuerpo Calloso/fisiología , Neurogénesis , Oligodendroglía/fisiología , Transmisión Sináptica , Células Madre Adultas/citología , Animales , Axones/fisiología , Señalización del Calcio , Proliferación Celular , Cuerpo Calloso/citología , Inmunohistoquímica , Masculino , Ratones Transgénicos , Microglía/citología , Microglía/fisiología , Microscopía Confocal , Oligodendroglía/citología , Técnicas de Placa-Clamp , Distribución Aleatoria , Sinapsis/fisiología , Potenciales SinápticosRESUMEN
: Glioblastoma is a primary Central Nervous System (CNS) malignancy with poor survival. Treatment options are scarce and despite the extremely heterogeneous nature of the disease, clinicians lack prognostic and predictive markers to characterize patients with different outcomes. Certain immunohistochemistry, FISH, or PCR-based molecular markers, including isocitrate dehydrogenase1/2 (IDH1/2) mutations, epidermal growth factor receptor variant III (EGFRvIII) mutation, vascular endothelial growth factor overexpression (VEGF) overexpression, or (O6-Methylguanine-DNA methyltransferase promoter) MGMT promoter methylation status, are well-described; however, their clinical usefulness and accuracy is limited, and tumor tissue samples are always necessary. Liquid biopsy is a developing field of diagnostics and patient follow up in multiple types of cancer. Fragments of circulating nucleic acids are collected in various forms from different bodily fluids, including serum, urine, or cerebrospinal fluid in order to measure the quality and quantity of these markers. Multiple types of nucleic acids can be analyzed using liquid biopsy. Circulating cell-free DNA, mitochondrial DNA, or the more stable long and small non-coding RNAs, circular RNAs, or microRNAs can be identified and measured by novel PCR and next-generation sequencing-based methods. These markers can be used to detect the previously described alterations in a minimally invasive method. These markers can be used to differentiate patients with poor or better prognosis, or to identify patients who do not respond to therapy. Liquid biopsy can be used to detect recurrent disease, often earlier than using imaging modalities. Liquid biopsy is a rapidly developing field, and similarly to other types of cancer, measuring circulating tumor-derived nucleic acids from biological fluid samples could be the future of differential diagnostics, patient stratification, and follow up in the future in glioblastoma as well.
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Biomarcadores de Tumor , Neoplasias del Sistema Nervioso Central/diagnóstico , Glioblastoma/diagnóstico , Biopsia Líquida , Ácidos Nucleicos Libres de Células , Neoplasias del Sistema Nervioso Central/etiología , Neoplasias del Sistema Nervioso Central/metabolismo , ADN de Neoplasias , Susceptibilidad a Enfermedades , Vesículas Extracelulares , Glioblastoma/etiología , Glioblastoma/metabolismo , Humanos , Biopsia Líquida/métodos , Biopsia Líquida/normas , Células Neoplásicas CirculantesRESUMEN
Exposure to physiological estrogens or xenoestrogens (e.g., zearalenone or bisphenol A) increases the risk for cancer. However, little information is available on their significance in ovarian cancer. We present a comprehensive study on the effect of estradiol, zearalenone and bisphenol A on the phenotype, mRNA, intracellular and cell-free miRNA expression of human epithelial ovarian cell lines. Estrogens induced a comparable effect on the rate of cell proliferation and migration as well as on the expression of estrogen-responsive genes (GREB1, CA12, DEPTOR, RBBP8) in the estrogen receptor α (ERα)-expressing PEO1 cell line, which was not observable in the absence of this receptor (in A2780 cells). The basal intracellular and cell-free expression of miR200s and miR203a was higher in PEO1, which was accompanied with low ZEB1 and high E-cadherin expression. These miRNAs showed a rapid but intermittent upregulation in response to estrogens that was diminished by an ERα-specific antagonist. The role of ERα in the regulation of the MIR200B-MIR200A-MIR429 locus was further supported by publicly available ChIP-seq data. MiRNA expression of cell lysates correlated well with cell-free miRNA expression. We conclude that cell-free miR200s might be promising biomarkers to assess estrogen sensitivity of ovarian cells.
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Carcinoma Epitelial de Ovario/genética , Receptor alfa de Estrógeno/genética , Estrógenos/genética , MicroARNs/genética , Biomarcadores de Tumor/genética , Cadherinas/genética , Carcinoma Epitelial de Ovario/patología , Línea Celular Tumoral , Movimiento Celular/genética , Proliferación Celular/genética , Endodesoxirribonucleasas/genética , Transición Epitelial-Mesenquimal/genética , Estradiol/metabolismo , Estrógenos/metabolismo , Femenino , Regulación Neoplásica de la Expresión Génica/genética , Humanos , Péptidos y Proteínas de Señalización Intracelular/genética , Proteínas de Neoplasias/genética , ARN Mensajero/genética , Homeobox 1 de Unión a la E-Box con Dedos de Zinc/genéticaRESUMEN
Liquid biopsy recently became a very promising diagnostic method that has several advantages over conventional invasive methods. Liquid biopsy may serve as a source of several important biomarkers including cell-free nucleic acids (cf-NAs). Cf-DNA is widely used in prenatal testing in order to characterize fetal genetic disorders. Analysis of cf-DNA may provide information about the mutation profile of tumor cells, while cell-free non-coding RNAs are promising biomarker candidates in the diagnosis and prognosis of cancer. Many of these markers have the potential to help clinicians in therapy selection and in the follow-up of patients. Thus, cf-NA-based diagnostics represent a new path in personalized medicine. Although several reviews are available in the field, most of them focus on a limited number of cf-NA types. In this review, we give an overview about all known cf-NAs including cf-DNA, cf-mtDNA and cell-free non-coding RNA (miRNA, lncRNA, circRNA, piRNA, YRNA, and vtRNA) by discussing their biogenesis, biological function and potential as biomarker candidates in liquid biopsy. We also outline possible future directions in the field.
Asunto(s)
Ácidos Nucleicos Libres de Células/genética , Exosomas/genética , Feto/metabolismo , Biopsia Líquida/métodos , Medicina de Precisión/métodos , Biomarcadores de Tumor/sangre , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Biomarcadores de Tumor/orina , Ácidos Nucleicos Libres de Células/sangre , Ácidos Nucleicos Libres de Células/metabolismo , Ácidos Nucleicos Libres de Células/orina , ADN Mitocondrial/sangre , ADN Mitocondrial/genética , ADN Mitocondrial/metabolismo , ADN Mitocondrial/orina , Exosomas/metabolismo , Femenino , Feto/patología , Humanos , MicroARNs/sangre , MicroARNs/genética , MicroARNs/metabolismo , Mutación , Embarazo , Pronóstico , ARN Largo no Codificante/sangre , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , ARN Largo no Codificante/orinaRESUMEN
Structurally different bis(imino)copper(i) complexes were prepared in a highly modular manner and utilized as copper-based photocatalysts in the ATRA reactions of styrenes and alkyl halides. The new photocatalysts showed good catalytic activity and ensured efficient chemical transformations.
RESUMEN
The discovery of cell-free DNA (cfDNA) dates back to 1948, when Mandel and Metais found it in the sera of cancer patients [...].