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1.
Cell ; 184(9): 2471-2486.e20, 2021 04 29.
Artículo en Inglés | MEDLINE | ID: mdl-33878291

RESUMEN

Metastasis has been considered as the terminal step of tumor progression. However, recent genomic studies suggest that many metastases are initiated by further spread of other metastases. Nevertheless, the corresponding pre-clinical models are lacking, and underlying mechanisms are elusive. Using several approaches, including parabiosis and an evolving barcode system, we demonstrated that the bone microenvironment facilitates breast and prostate cancer cells to further metastasize and establish multi-organ secondary metastases. We uncovered that this metastasis-promoting effect is driven by epigenetic reprogramming that confers stem cell-like properties on cancer cells disseminated from bone lesions. Furthermore, we discovered that enhanced EZH2 activity mediates the increased stemness and metastasis capacity. The same findings also apply to single cell-derived populations, indicating mechanisms distinct from clonal selection. Taken together, our work revealed an unappreciated role of the bone microenvironment in metastasis evolution and elucidated an epigenomic reprogramming process driving terminal-stage, multi-organ metastases.


Asunto(s)
Neoplasias Óseas/secundario , Neoplasias de la Mama/patología , Metástasis de la Neoplasia , Neoplasias de la Próstata/patología , Microambiente Tumoral , Animales , Apoptosis , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Neoplasias Óseas/genética , Neoplasias Óseas/metabolismo , Neoplasias de la Mama/genética , Neoplasias de la Mama/metabolismo , Proliferación Celular , Progresión de la Enfermedad , Femenino , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos NOD , Ratones Desnudos , Ratones SCID , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/metabolismo , Células Tumorales Cultivadas , Ensayos Antitumor por Modelo de Xenoinjerto
2.
Cell ; 162(4): 808-22, 2015 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-26255771

RESUMEN

Dendritic spines are postsynaptic compartments of excitatory synapses that undergo dynamic changes during development, including rapid spinogenesis in early postnatal life and significant pruning during adolescence. Spine pruning defects have been implicated in developmental neurological disorders such as autism, yet much remains to be uncovered regarding its molecular mechanism. Here, we show that spine pruning and maturation in the mouse somatosensory cortex are coordinated via the cadherin/catenin cell adhesion complex and bidrectionally regulated by sensory experience. We further demonstrate that locally enhancing cadherin/catenin-dependent adhesion or photo-stimulating a contacting channelrhodopsin-expressing axon stabilized the manipulated spine and eliminated its neighbors, an effect requiring cadherin/catenin-dependent adhesion. Importantly, we show that differential cadherin/catenin-dependent adhesion between neighboring spines biased spine fate in vivo. These results suggest that activity-induced inter-spine competition for ß-catenin provides specificity for concurrent spine maturation and elimination and thus is critical for the molecular control of spine pruning during neural circuit refinement.


Asunto(s)
Cadherinas/metabolismo , Cateninas/metabolismo , Espinas Dendríticas/metabolismo , Corteza Somatosensorial/citología , Animales , Trastorno del Espectro Autista/metabolismo , Encéfalo/crecimiento & desarrollo , Encéfalo/metabolismo , Cadherinas/genética , Cateninas/genética , Ratones , Complejos Multiproteicos/metabolismo , Neuronas/metabolismo , Células Piramidales/metabolismo , Corteza Somatosensorial/metabolismo , Vibrisas/lesiones
3.
Cell ; 159(1): 200-214, 2014 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-25259927

RESUMEN

Invertebrate model systems are powerful tools for studying human disease owing to their genetic tractability and ease of screening. We conducted a mosaic genetic screen of lethal mutations on the Drosophila X chromosome to identify genes required for the development, function, and maintenance of the nervous system. We identified 165 genes, most of whose function has not been studied in vivo. In parallel, we investigated rare variant alleles in 1,929 human exomes from families with unsolved Mendelian disease. Genes that are essential in flies and have multiple human homologs were found to be likely to be associated with human diseases. Merging the human data sets with the fly genes allowed us to identify disease-associated mutations in six families and to provide insights into microcephaly associated with brain dysgenesis. This bidirectional synergism between fly genetics and human genomics facilitates the functional annotation of evolutionarily conserved genes involved in human health.


Asunto(s)
Enfermedad/genética , Drosophila melanogaster/genética , Pruebas Genéticas , Patrón de Herencia , Interferencia de ARN , Animales , Modelos Animales de Enfermedad , Humanos , Cromosoma X
4.
Proc Natl Acad Sci U S A ; 121(11): e2312136121, 2024 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-38446848

RESUMEN

Anxiety is a remarkably common condition among patients with pharyngitis, but the relationship between these disorders has received little research attention, and the underlying neural mechanisms remain unknown. Here, we show that the densely innervated pharynx transmits signals induced by pharyngeal inflammation to glossopharyngeal and vagal sensory neurons of the nodose/jugular/petrosal (NJP) superganglia in mice. Specifically, the NJP superganglia project to norepinephrinergic neurons in the nucleus of the solitary tract (NTSNE). These NTSNE neurons project to the ventral bed nucleus of the stria terminalis (vBNST) that induces anxiety-like behaviors in a murine model of pharyngeal inflammation. Inhibiting this pharynx→NJP→NTSNE→vBNST circuit can alleviate anxiety-like behaviors associated with pharyngeal inflammation. This study thus defines a pharynx-to-brain axis that mechanistically links pharyngeal inflammation and emotional response.


Asunto(s)
Faringitis , Faringe , Humanos , Animales , Ratones , Ansiedad , Encéfalo , Células Receptoras Sensoriales , Inflamación
5.
Proc Natl Acad Sci U S A ; 121(28): e2322972121, 2024 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-38968116

RESUMEN

Rapid accumulation of repair factors at DNA double-strand breaks (DSBs) is essential for DSB repair. Several factors involved in DSB repair have been found undergoing liquid-liquid phase separation (LLPS) at DSB sites to facilitate DNA repair. RNF168, a RING-type E3 ubiquitin ligase, catalyzes H2A.X ubiquitination for recruiting DNA repair factors. Yet, whether RNF168 undergoes LLPS at DSB sites remains unclear. Here, we identified K63-linked polyubiquitin-triggered RNF168 condensation which further promoted RNF168-mediated DSB repair. RNF168 formed liquid-like condensates upon irradiation in the nucleus while purified RNF168 protein also condensed in vitro. An intrinsically disordered region containing amino acids 460-550 was identified as the essential domain for RNF168 condensation. Interestingly, LLPS of RNF168 was significantly enhanced by K63-linked polyubiquitin chains, and LLPS largely enhanced the RNF168-mediated H2A.X ubiquitination, suggesting a positive feedback loop to facilitate RNF168 rapid accumulation and its catalytic activity. Functionally, LLPS deficiency of RNF168 resulted in delayed recruitment of 53BP1 and BRCA1 and subsequent impairment in DSB repair. Taken together, our finding demonstrates the pivotal effect of LLPS in RNF168-mediated DSB repair.


Asunto(s)
Reparación del ADN , Ubiquitina-Proteína Ligasas , Humanos , Roturas del ADN de Doble Cadena , Histonas/metabolismo , Histonas/genética , Poliubiquitina/metabolismo , Proteína 1 de Unión al Supresor Tumoral P53/metabolismo , Proteína 1 de Unión al Supresor Tumoral P53/genética , Ubiquitina/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo , Ubiquitina-Proteína Ligasas/genética , Ubiquitinación
6.
Hum Mol Genet ; 2024 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-39277796

RESUMEN

Genomic copy-number variations (CNVs) that can cause neurodevelopmental disorders often encompass many genes, which complicates our understanding of how individual genes within a CNV contribute to pathology. MECP2 duplication syndrome (MDS or MRXSL in OMIM; OMIM#300260) is one such CNV disorder caused by duplications spanning methyl CpG-binding protein 2 (MECP2) and other genes on Xq28. Using an antisense oligonucleotide (ASO) to normalize MECP2 dosage is sufficient to rescue abnormal neurological phenotypes in mouse models overexpressing MECP2 alone, implicating the importance of increased MECP2 dosage within CNVs of Xq28. However, because MDS CNVs span MECP2 and additional genes, we generated human neurons from multiple MDS patient-derived induced pluripotent cells (iPSCs) to evaluate the benefit of using an ASO against MECP2 in a MDS human neuronal context. Importantly, we identified a signature of genes that is partially and qualitatively modulated upon ASO treatment, pinpointed genes sensitive to MeCP2 function, and altered in a model of Rett syndrome, a neurological disorder caused by loss of MeCP2 function. Furthermore, the signature contained genes that are aberrantly altered in unaffected control human neurons upon MeCP2 depletion, revealing gene expression programs qualitatively sensitive to MeCP2 levels in human neurons. Lastly, ASO treatment led to a partial rescue of abnormal neuronal morphology in MDS neurons. All together, these data demonstrate that ASOs targeting MECP2 benefit human MDS neurons. Moreover, our study establishes a paradigm by which to evaluate the contribution of individual genes within a CNV to pathogenesis and to assess their potential as a therapeutic target.

7.
EMBO J ; 40(7): e106106, 2021 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-33709453

RESUMEN

A critical question in neurodegeneration is why the accumulation of disease-driving proteins causes selective neuronal loss despite their brain-wide expression. In Spinocerebellar ataxia type 1 (SCA1), accumulation of polyglutamine-expanded Ataxin-1 (ATXN1) causes selective degeneration of cerebellar and brainstem neurons. Previous studies revealed that inhibiting Msk1 reduces phosphorylation of ATXN1 at S776 as well as its levels leading to improved cerebellar function. However, there are no regulators that modulate ATXN1 in the brainstem-the brain region whose pathology is most closely linked to premature death. To identify new regulators of ATXN1, we performed genetic screens and identified a transcription factor-kinase axis (ZBTB7B-RSK3) that regulates ATXN1 levels. Unlike MSK1, RSK3 is highly expressed in the human and mouse brainstems where it regulates Atxn1 by phosphorylating S776. Reducing Rsk3 rescues brainstem-associated pathologies and deficits, and lowering Rsk3 and Msk1 together improves cerebellar and brainstem function in an SCA1 mouse model. Our results demonstrate that selective vulnerability of brain regions in SCA1 is governed by region-specific regulators of ATXN1, and targeting multiple regulators could rescue multiple degenerating brain areas.


Asunto(s)
Tronco Encefálico/metabolismo , Cerebelo/metabolismo , Proteínas de Unión al ADN/metabolismo , Proteínas Quinasas S6 Ribosómicas 90-kDa/metabolismo , Ataxias Espinocerebelosas/metabolismo , Factores de Transcripción/metabolismo , Animales , Ataxina-1/genética , Ataxina-1/metabolismo , Línea Celular Tumoral , Células Cultivadas , Proteínas de Unión al ADN/genética , Drosophila melanogaster , Células HEK293 , Humanos , Ratones , Fosforilación , Estabilidad Proteica , Proteínas Quinasas S6 Ribosómicas 90-kDa/genética , Ataxias Espinocerebelosas/genética , Factores de Transcripción/genética
8.
Lancet ; 403(10423): 249-260, 2024 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-38048786

RESUMEN

BACKGROUND: Unmet medical needs remain in patients with red blood cell transfusion-dependent (RBC-TD) lower-risk myelodysplastic syndromes (LR-MDS) who are not responding to or are ineligible for erythropoiesis-stimulating agents (ESAs). Imetelstat, a competitive telomerase inhibitor, showed promising results in a phase 2 trial. We aimed to compare the RBC transfusion independence (RBC-TI) rate with imetelstat versus placebo in patients with RBC-TD LR-MDS. METHODS: In phase 3 of IMerge, a double-blind, placebo-controlled trial conducted in 118 sites including university hospitals, cancer centres, and outpatient clinics in 17 countries, patients (aged ≥18 years) with ESA-relapsed, ESA-refractory, or ESA-ineligible LR-MDS (low or intermediate-1 risk disease as per International Prognostic Scoring System [IPSS] criteria) were randomly assigned via a computer-generated schedule (2:1) to receive imetelstat 7·5 mg/kg or placebo, administered as a 2-h intravenous infusion, every 4 weeks until disease progression, unacceptable toxic effects, or withdrawal of consent. Randomisation was stratified by previous RBC transfusion burden and IPSS risk group. Patients, investigators, and those analysing the data were masked to group assignment. The primary endpoint was 8-week RBC-TI, defined as the proportion of patients without RBC transfusions for at least 8 consecutive weeks starting on the day of randomisation until subsequent anti-cancer therapy, if any. Primary efficacy analyses were performed in the intention-to-treat population, and safety analyses were conducted in patients who received at least one dose of trial medication or placebo. This trial is registered with ClinicalTrials.gov (NCT02598661; substudy active and recruiting). FINDINGS: Between Sept 11, 2019, and Oct 13, 2021, 178 patients were enrolled and randomly assigned (118 to imetelstat and 60 to placebo). 111 (62%) were male and 67 (38%) were female. 91 (77%) of 118 patients had discontinued treatment by data cutoff in the imetelstat group versus 45 (75%) in the placebo group; a further one patient in the placebo group did not receive treatment. Median follow-up was 19·5 months (IQR 12·0-23·4) in the imetelstat group and 17·5 months (12·1-22·7) in the placebo group. In the imetelstat group, 47 (40% [95% CI 30·9-49·3]) patients had an RBC-TI of at least 8 weeks versus nine (15% [7·1-26·6]) in the placebo group (rate difference 25% [9·9 to 36·9]; p=0·0008). Overall, 107 (91%) of 118 patients receiving imetelstat and 28 (47%) of 59 patients receiving placebo had grade 3-4 treatment-emergent adverse events. The most common treatment-emergent grade 3-4 adverse events in patients taking imetelstat were neutropenia (80 [68%] patients who received imetelstat vs two [3%] who received placebo) and thrombocytopenia (73 [62%] vs five [8%]). No treatment-related deaths were reported. INTERPRETATION: Imetelstat offers a novel mechanism of action with durable transfusion independence (approximately 1 year) and disease-modifying activity for heavily transfused patients with LR-MDS who are not responding to or are ineligible for ESAs. FUNDING: Janssen Research & Development before April 18, 2019, and Geron Corporation thereafter.


Asunto(s)
Síndromes Mielodisplásicos , Oligonucleótidos , Trombocitopenia , Humanos , Masculino , Femenino , Adolescente , Adulto , Resultado del Tratamiento , Eritropoyesis , Síndromes Mielodisplásicos/tratamiento farmacológico , Trombocitopenia/tratamiento farmacológico , Método Doble Ciego , Protocolos de Quimioterapia Combinada Antineoplásica
9.
Brief Bioinform ; 25(1)2023 11 22.
Artículo en Inglés | MEDLINE | ID: mdl-38113079

RESUMEN

Millions of RNA sequencing samples have been deposited into public databases, providing a rich resource for biological research. These datasets encompass tens of thousands of experiments and offer comprehensive insights into human cellular regulation. However, a major challenge is how to integrate these experiments that acquired at different conditions. We propose a new statistical tool based on beta-binomial distributions that can construct robust gene co-regulation network (CoRegNet) across tens of thousands of experiments. Our analysis of over 12 000 experiments involving human tissues and cells shows that CoRegNet significantly outperforms existing gene co-expression-based methods. Although the majority of the genes are linearly co-regulated, we did discover an interesting set of genes that are non-linearly co-regulated; half of the time they change in the same direction and the other half they change in the opposite direction. Additionally, we identified a set of gene pairs that follows the Simpson's paradox. By utilizing public domain data, CoRegNet offers a powerful approach for identifying functionally related gene pairs, thereby revealing new biological insights.


Asunto(s)
Redes Reguladoras de Genes , Modelos Estadísticos , Humanos , RNA-Seq , Análisis de Secuencia de ARN/métodos , Perfilación de la Expresión Génica/métodos
10.
Brief Bioinform ; 25(1)2023 11 22.
Artículo en Inglés | MEDLINE | ID: mdl-38197309

RESUMEN

Although some pyroptosis-related (PR) prognostic models for cancers have been reported, pyroptosis-based features have not been fully discovered at the single-cell level in hepatocellular carcinoma (HCC). In this study, by deeply integrating single-cell and bulk transcriptome data, we systematically investigated significance of the shared pyroptotic signature at both single-cell and bulk levels in HCC prognosis. Based on the pyroptotic signature, a robust PR risk system was constructed to quantify the prognostic risk of individual patient. To further verify capacity of the pyroptotic signature on predicting patients' prognosis, an attention mechanism-based deep neural network classification model was constructed. The mechanisms of prognostic difference in the patients with distinct PR risk were dissected on tumor stemness, cancer pathways, transcriptional regulation, immune infiltration and cell communications. A nomogram model combining PR risk with clinicopathologic data was constructed to evaluate the prognosis of individual patients in clinic. The PR risk could also evaluate therapeutic response to neoadjuvant therapies in HCC patients. In conclusion, the constructed PR risk system enables a comprehensive assessment of tumor microenvironment characteristics, accurate prognosis prediction and rational therapeutic options in HCC.


Asunto(s)
Carcinoma Hepatocelular , Aprendizaje Profundo , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/terapia , Transcriptoma , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/terapia , Comunicación Celular , Microambiente Tumoral/genética
11.
Brief Bioinform ; 24(6)2023 09 22.
Artículo en Inglés | MEDLINE | ID: mdl-37864296

RESUMEN

Advances in single-cell sequencing and data analysis have made it possible to infer biological trajectories spanning heterogeneous cell populations based on transcriptome variation. These trajectories yield a wealth of novel insights into dynamic processes such as development and differentiation. However, trajectory analysis relies on an assumption of trajectory continuity, and experimental limitations preclude some real-world scenarios from meeting this condition. The current lack of assessment metrics makes it difficult to ascertain if/when a given trajectory deviates from continuity, and what impact such a divergence would have on inference accuracy is unclear. By analyzing simulated breaks introduced into in silico and real single-cell data, we found that discontinuity caused precipitous drops in the accuracy of trajectory inference. We then generate a simple scoring algorithm for assessing trajectory continuity, and found that continuity assessments in real-world cases of intestinal stem cell development and CD8 + T cells differentiation efficiently identifies trajectories consistent with empirical knowledge. This assessment approach can also be used in cases where a priori knowledge is lacking to screen a pool of inferred lineages for their adherence to presumed continuity, and serve as a means for weighing higher likelihood trajectories for validation via empirical studies, as exemplified by our case studies in psoriatic arthritis and acute kidney injury. This tool is freely available through github at qingshanni/scEGRET.


Asunto(s)
Algoritmos , Transcriptoma , Diferenciación Celular , Análisis de la Célula Individual
12.
Am J Pathol ; 194(6): 879-893, 2024 06.
Artículo en Inglés | MEDLINE | ID: mdl-38417698

RESUMEN

Cholestatic liver diseases encompass a range of organic damages, metabolic disorders, and dysfunctions within the hepatobiliary system, arising from various pathogenic causes. These factors contribute to disruptions in bile production, secretion, and excretion. Cholestatic liver diseases can be classified into intrahepatic and extrahepatic cholestasis, according to the location of occurrence. The etiology of cholestatic liver diseases is complex, and includes drugs, poisons, viruses, parasites, bacteria, autoimmune responses, tumors, and genetic metabolism. The pathogenesis of cholelstatic liver disease is not completely clarified, and effective therapy is lacking. Clarifying its mechanism to find more effective therapeutic targets and drugs is an unmet need. Increasing evidence demonstrates that miRNA and long noncoding RNA are involved in the progression of cholestatic liver diseases. This review provides a comprehensive summary of the research progress on the roles of miRNA and long noncoding RNA in cholestatic liver diseases. The aim of the review is to enhance the understanding of their potential diagnostic, therapeutic, and prognostic value for patients with cholestasis.


Asunto(s)
Colestasis , MicroARNs , ARN Largo no Codificante , Humanos , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , MicroARNs/genética , MicroARNs/metabolismo , Colestasis/genética , Colestasis/metabolismo , Colestasis/patología , Animales , Hepatopatías/genética , Hepatopatías/metabolismo , Hepatopatías/patología
13.
Immunity ; 44(3): 568-581, 2016 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-26921109

RESUMEN

Upon antigen engagement, augmented cytosolic reactive oxygen species (ROS) are needed to achieve optimal T cell receptor (TCR) signaling. However, uncontrolled ROS production is a prominent cause of necrosis, which elicits hyper-inflammation and tissue damage. Hence, it is critical to program activated T cells to achieve ROS equilibrium. Here, we determined that miR-23a is indispensable for effector CD4(+) T cell expansion, particularly by providing early protection from excessive necrosis. Mechanistically, miR-23a targeted PPIF, gatekeeper of the mitochondria permeability transition pore, thereby restricting ROS flux and maintaining mitochondrial integrity. Upon acute Listeria monocytogenes infection, deleting miR-23a in T cells resulted in excessive inflammation, massive liver damage, and a marked mortality increase, which highlights the essential role of miR-23a in maintaining immune homeostasis.


Asunto(s)
Linfocitos T CD4-Positivos/inmunología , Listeria monocytogenes/inmunología , Listeriosis/inmunología , Hígado/patología , MicroARNs/metabolismo , Mitocondrias/metabolismo , Animales , Células Cultivadas , Peptidil-Prolil Isomerasa F , Ciclofilinas/metabolismo , Homeostasis , Ratones , Ratones Transgénicos , MicroARNs/genética , Proteínas de Transporte de Membrana Mitocondrial/metabolismo , Poro de Transición de la Permeabilidad Mitocondrial , Necrosis , ARN Interferente Pequeño/genética , Especies Reactivas de Oxígeno/metabolismo , Receptores de Antígenos de Linfocitos T/metabolismo , Transducción de Señal/genética
14.
Immunity ; 44(2): 422-37, 2016 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-26885862

RESUMEN

Dendritic cells (DCs) orchestrate complex membrane trafficking through an interconnected transportation network linked together by Rab GTPases. Through a tandem affinity purification strategy and mass spectrometry, we depicted an interactomic landscape of major members of the mammalian Rab GTPase family. When complemented with imaging tools, this proteomic analysis provided a global view of intracellular membrane organization. Driven by this analysis, we investigated dynamic changes to the Rab32 subnetwork in DCs induced by L. monocytogenes infection and uncovered an essential role of this subnetwork in controlling the intracellular proliferation of L. monocytogenes. Mechanistically, Rab32 formed a persistent complex with two interacting proteins, PHB and PHB2, to encompass bacteria both during early phagosome formation and after L. monocytogenes escaped the original containment vacuole. Collectively, we have provided a functional compartmentalization overview and an organizational framework of intracellular Rab-mediated vesicle trafficking that can serve as a resource for future investigations.


Asunto(s)
Células Dendríticas/inmunología , Listeria monocytogenes/inmunología , Listeriosis/inmunología , Complejos Multiproteicos/metabolismo , Proteínas de Unión al GTP rab/metabolismo , Aciltransferasas/metabolismo , Animales , Antiinfecciosos/uso terapéutico , Línea Celular , Biología Computacional , Contención de Riesgos Biológicos , Células Dendríticas/microbiología , Listeria monocytogenes/crecimiento & desarrollo , Listeriosis/tratamiento farmacológico , Ratones , Prohibitinas , Transporte de Proteínas , Proteínas Represoras/metabolismo , Vacuolas/metabolismo
15.
Methods ; 231: 226-236, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-39413889

RESUMEN

Although spatial transcriptomics data provide valuable insights into gene expression profiles and the spatial structure of tissues, most studies rely solely on gene expression information, underutilizing the spatial data. To fully leverage the potential of spatial transcriptomics and graph neural networks, the DGSI (Deep Graph Structure Infomax) model is proposed. This innovative graph data processing model uses graph convolutional neural networks and employs an unsupervised learning approach. It maximizes the mutual information between graph-level and node-level representations, emphasizing flexible sampling and aggregation of nodes and their neighbors. This effectively captures and incorporates local information from nodes into the overall graph structure. Additionally, this paper developed the DGSIST framework, an unsupervised cell clustering method that integrates the DGSI model, SVD dimensionality reduction algorithm, and k-means++ clustering algorithm. This aims to identify cell types accurately. DGSIST fully uses spatial transcriptomics data and outperforms existing methods in accuracy. Demonstrations of DGSIST's capability across various tissue types and technological platforms have shown its effectiveness in accurately identifying spatial domains in multiple tissue sections. Compared to other spatial clustering methods, DGSIST excels in cell clustering and effectively eliminates batch effects without needing batch correction. DGSIST excels in spatial clustering analysis, spatial variation identification, and differential gene expression detection and directly applies to graph analysis tasks, such as node classification, link prediction, or graph clustering. Anticipation lies in the contribution of the DGSIST framework to a deeper understanding of the spatial organizational structures of diseases such as cancer.


Asunto(s)
Algoritmos , Transcriptoma , Análisis por Conglomerados , Transcriptoma/genética , Humanos , Perfilación de la Expresión Génica/métodos , Redes Neurales de la Computación , Aprendizaje Automático no Supervisado , Biología Computacional/métodos
16.
Nature ; 565(7741): 654-658, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30675060

RESUMEN

Diffuse gliomas are the most common malignant brain tumours in adults and include glioblastomas and World Health Organization (WHO) grade II and grade III tumours (sometimes referred to as lower-grade gliomas). Genetic tumour profiling is used to classify disease and guide therapy1,2, but involves brain surgery for tissue collection; repeated tumour biopsies may be necessary for accurate genotyping over the course of the disease3-10. While the detection of circulating tumour DNA (ctDNA) in the blood of patients with primary brain tumours remains challenging11,12, sequencing of ctDNA from the cerebrospinal fluid (CSF) may provide an alternative way to genotype gliomas with lower morbidity and cost13,14. We therefore evaluated the representation of the glioma genome in CSF from 85 patients with gliomas who underwent a lumbar puncture because they showed neurological signs or symptoms. Here we show that tumour-derived DNA was detected in CSF from 42 out of 85 patients (49.4%) and was associated with disease burden and adverse outcome. The genomic landscape of glioma in the CSF included a broad spectrum of genetic alterations and closely resembled the genomes of tumour biopsies. Alterations that occur early during tumorigenesis, such as co-deletion of chromosome arms 1p and 19q (1p/19q codeletion) and mutations in the metabolic genes isocitrate dehydrogenase 1 (IDH1) or IDH21,2, were shared in all matched ctDNA-positive CSF-tumour pairs, whereas growth factor receptor signalling pathways showed considerable evolution. The ability to monitor the evolution of the glioma genome through a minimally invasive technique could advance the clinical development and use of genotype-directed therapies for glioma, one of the most aggressive human cancers.


Asunto(s)
Evolución Molecular , Glioma/líquido cefalorraquídeo , Glioma/genética , Biopsia Líquida , Mutación , Genes Relacionados con las Neoplasias/genética , Genoma Humano/genética , Genómica , Glioblastoma/líquido cefalorraquídeo , Glioblastoma/genética , Glioblastoma/patología , Glioma/patología , Humanos , Clasificación del Tumor
17.
Mol Ther ; 32(8): 2778-2797, 2024 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-38822524

RESUMEN

Dysregulated T cell activation underpins the immunopathology of rheumatoid arthritis (RA), yet the machineries that orchestrate T cell effector program remain incompletely understood. Herein, we leveraged bulk and single-cell RNA sequencing data from RA patients and validated protein disulfide isomerase family A member 3 (PDIA3) as a potential therapeutic target. PDIA3 is remarkably upregulated in pathogenic CD4 T cells derived from RA patients and positively correlates with C-reactive protein level and disease activity score 28. Pharmacological inhibition or genetic ablation of PDIA3 alleviates RA-associated articular pathology and autoimmune responses. Mechanistically, T cell receptor signaling triggers intracellular calcium flux to activate NFAT1, a process that is further potentiated by Wnt5a under RA settings. Activated NFAT1 then directly binds to the Pdia3 promoter to enhance the expression of PDIA3, which complexes with STAT1 or PKM2 to facilitate their nuclear import for transcribing T helper 1 (Th1) and Th17 lineage-related genes, respectively. This non-canonical regulatory mechanism likely occurs under pathological conditions, as PDIA3 could only be highly induced following aberrant external stimuli. Together, our data support that targeting PDIA3 is a vital strategy to mitigate autoimmune diseases, such as RA, in clinical settings.


Asunto(s)
Artritis Reumatoide , Proteína Disulfuro Isomerasas , Factor de Transcripción STAT1 , Proteína Disulfuro Isomerasas/metabolismo , Proteína Disulfuro Isomerasas/genética , Humanos , Artritis Reumatoide/metabolismo , Ratones , Animales , Factor de Transcripción STAT1/metabolismo , Proteínas de la Membrana/metabolismo , Proteínas de la Membrana/genética , Transporte Activo de Núcleo Celular , Proteínas Portadoras/metabolismo , Transducción de Señal , Proteínas de Unión a Hormona Tiroide , Factores de Transcripción NFATC/metabolismo , Activación de Linfocitos , Hormonas Tiroideas/metabolismo , Regulación de la Expresión Génica , Células Th17/metabolismo , Células Th17/inmunología , Células TH1/inmunología , Células TH1/metabolismo , Modelos Animales de Enfermedad , Piruvato Quinasa
18.
Cell Mol Life Sci ; 81(1): 205, 2024 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-38703204

RESUMEN

BACKGROUND: Exposure to chronic psychological stress (CPS) is a risk factor for thrombotic cardiocerebrovascular diseases (CCVDs). The expression and activity of the cysteine cathepsin K (CTSK) are upregulated in stressed cardiovascular tissues, and we investigated whether CTSK is involved in chronic stress-related thrombosis, focusing on stress serum-induced endothelial apoptosis. METHODS AND RESULTS: Eight-week-old wild-type male mice (CTSK+/+) randomly divided to non-stress and 3-week restraint stress groups received a left carotid artery iron chloride3 (FeCl3)-induced thrombosis injury for biological and morphological evaluations at specific timepoints. On day 21 post-stress/injury, the stress had enhanced the arterial thrombi weights and lengths, in addition to harmful alterations of plasma ADAMTS13, von Willebrand factor, and plasminogen activation inhibitor-1, plus injured-artery endothelial loss and CTSK protein/mRNA expression. The stressed CTSK+/+ mice had increased levels of injured arterial cleaved Notch1, Hes1, cleaved caspase8, matrix metalloproteinase-9/-2, angiotensin type 1 receptor, galactin3, p16IN4A, p22phox, gp91phox, intracellular adhesion molecule-1, TNF-α, MCP-1, and TLR-4 proteins and/or genes. Pharmacological and genetic inhibitions of CTSK ameliorated the stress-induced thrombus formation and the observed molecular and morphological changes. In cultured HUVECs, CTSK overexpression and silencing respectively increased and mitigated stressed-serum- and H2O2-induced apoptosis associated with apoptosis-related protein changes. Recombinant human CTSK degraded γ-secretase substrate in a dose-dependent manor and activated Notch1 and Hes1 expression upregulation. CONCLUSIONS: CTSK appeared to contribute to stress-related thrombosis in mice subjected to FeCl3 stress, possibly via the modulation of vascular inflammation, oxidative production and apoptosis, suggesting that CTSK could be an effective therapeutic target for CPS-related thrombotic events in patients with CCVDs.


Asunto(s)
Apoptosis , Catepsina K , Cloruros , Modelos Animales de Enfermedad , Compuestos Férricos , Trombosis , Animales , Humanos , Masculino , Ratones , Proteína ADAMTS13/metabolismo , Proteína ADAMTS13/genética , Catepsina K/metabolismo , Catepsina K/genética , Cloruros/metabolismo , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Ratones Endogámicos C57BL , Ratones Noqueados , Inhibidor 1 de Activador Plasminogénico/metabolismo , Inhibidor 1 de Activador Plasminogénico/genética , Estrés Psicológico/complicaciones , Estrés Psicológico/metabolismo , Trombosis/metabolismo , Trombosis/patología , Factor de Transcripción HES-1/metabolismo , Factor de Transcripción HES-1/genética
19.
Curr Issues Mol Biol ; 46(7): 6533-6565, 2024 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-39057032

RESUMEN

Technological advancements in cell-free DNA (cfDNA) liquid biopsy have triggered exponential growth in numerous clinical applications. While cfDNA-based liquid biopsy has made significant strides in personalizing cancer treatment, the exploration and translation of epigenetics in liquid biopsy to clinical practice is still nascent. This comprehensive review seeks to provide a broad yet in-depth narrative of the present status of epigenetics in cfDNA liquid biopsy and its associated challenges. It highlights the potential of epigenetics in cfDNA liquid biopsy technologies with the hopes of enhancing its clinical translation. The momentum of cfDNA liquid biopsy technologies in recent years has propelled epigenetics to the forefront of molecular biology. We have only begun to reveal the true potential of epigenetics in both our understanding of disease and leveraging epigenetics in the diagnostic and therapeutic domains. Recent clinical applications of epigenetics-based cfDNA liquid biopsy revolve around DNA methylation in screening and early cancer detection, leading to the development of multi-cancer early detection tests and the capability to pinpoint tissues of origin. The clinical application of epigenetics in cfDNA liquid biopsy in minimal residual disease, monitoring, and surveillance are at their initial stages. A notable advancement in fragmentation patterns analysis has created a new avenue for epigenetic biomarkers. However, the widespread application of cfDNA liquid biopsy has many challenges, including biomarker sensitivity, specificity, logistics including infrastructure and personnel, data processing, handling, results interpretation, accessibility, and cost effectiveness. Exploring and translating epigenetics in cfDNA liquid biopsy technology can transform our understanding and perception of cancer prevention and management. cfDNA liquid biopsy has great potential in precision oncology to revolutionize conventional ways of early cancer detection, monitoring residual disease, treatment response, surveillance, and drug development. Adapting the implementation of liquid biopsy workflow to the local policy worldwide and developing point-of-care testing holds great potential to overcome global cancer disparity and improve cancer outcomes.

20.
Artículo en Inglés | MEDLINE | ID: mdl-38908733

RESUMEN

BACKGROUND & AIMS: Post-acute COVID-19 syndrome (PACS) is associated with sleep disturbance, but treatment options are limited. The etiology of PACS may be secondary to alterations in the gut microbiome. Here, we report the efficacy of fecal microbiota transplantation (FMT) in alleviating post-COVID insomnia symptoms in a nonrandomized, open-label prospective interventional study. METHODS: Between September 22, 2022, and May 22, 2023, we recruited 60 PACS patients with insomnia defined as Insomnia Severity Index (ISI) ≥8 and assigned them to the FMT group (FMT at weeks 0, 2, 4, and 8; n = 30) or the control group (n = 30). The primary outcome was clinical remission defined by an ISI of <8 at 12 weeks. Secondary outcomes included changes in the Pittsburgh Sleep Quality Index, Generalized Anxiety Disorder-7 scale, Epworth Sleepiness Scale, Multidimensional Fatigue Inventory, blood cortisol and melatonin, and gut microbiome analysis on metagenomic sequencing. RESULTS: At week 12, more patients in the FMT than the control group had insomnia remission (37.9% vs 10.0%; P = .018). The FMT group showed a decrease in ISI score (P < .0001), Pittsburgh Sleep Quality Index (P < .0001), Generalized Anxiety Disorder-7 scale (P = .0019), Epworth Sleepiness Scale (P = .0057), and blood cortisol concentration (P = .035) from baseline to week 12, but there was no significant change in the control group. There was enrichment of bacteria such as Gemmiger formicilis and depletion of microbial pathways producing menaquinol derivatives after FMT. The gut microbiome profile resembled that of the donor in FMT responders but not in nonresponders at week 12. There was no serious adverse event. CONCLUSIONS: This pilot study showed that FMT could be effective and safe in alleviating post-COVID insomnia, and further clinical trials are warranted. CLINICALTRIALS: gov, Number: NCT05556733.

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