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1.
Immunity ; 57(5): 1124-1140.e9, 2024 May 14.
Article in English | MEDLINE | ID: mdl-38636522

ABSTRACT

Signaling through Notch receptors intrinsically regulates tumor cell development and growth. Here, we studied the role of the Notch ligand Jagged2 on immune evasion in non-small cell lung cancer (NSCLC). Higher expression of JAG2 in NSCLC negatively correlated with survival. In NSCLC pre-clinical models, deletion of Jag2, but not Jag1, in cancer cells attenuated tumor growth and activated protective anti-tumor T cell responses. Jag2-/- lung tumors exhibited higher frequencies of macrophages that expressed immunostimulatory mediators and triggered T cell-dependent anti-tumor immunity. Mechanistically, Jag2 ablation promoted Nr4a-mediated induction of Notch ligands DLL1/4 on cancer cells. DLL1/4-initiated Notch1/2 signaling in macrophages induced the expression of transcription factor IRF4 and macrophage immunostimulatory functionality. IRF4 expression was required for the anti-tumor effects of Jag2 deletion in lung tumors. Antibody targeting of Jagged2 inhibited tumor growth and activated IRF4-driven macrophage-mediated anti-tumor immunity. Thus, Jagged2 orchestrates immunosuppressive systems in NSCLC that can be overcome to incite macrophage-mediated anti-tumor immunity.


Subject(s)
Carcinoma, Non-Small-Cell Lung , Interferon Regulatory Factors , Jagged-2 Protein , Lung Neoplasms , Mice, Knockout , Tumor-Associated Macrophages , Animals , Humans , Mice , Calcium-Binding Proteins/metabolism , Calcium-Binding Proteins/genetics , Carcinoma, Non-Small-Cell Lung/immunology , Carcinoma, Non-Small-Cell Lung/pathology , Carcinoma, Non-Small-Cell Lung/metabolism , Cell Line, Tumor , Interferon Regulatory Factors/metabolism , Interferon Regulatory Factors/genetics , Jagged-1 Protein/metabolism , Jagged-1 Protein/genetics , Jagged-2 Protein/metabolism , Jagged-2 Protein/genetics , Jagged-2 Protein/immunology , Lung Neoplasms/immunology , Lung Neoplasms/pathology , Lung Neoplasms/genetics , Macrophages/immunology , Macrophages/metabolism , Mice, Inbred C57BL , Receptor, Notch1/metabolism , Receptor, Notch1/genetics , Receptors, Notch/metabolism , Signal Transduction , Tumor Escape/immunology , Tumor-Associated Macrophages/immunology , Tumor-Associated Macrophages/metabolism
2.
Cell ; 167(3): 774-788.e17, 2016 Oct 20.
Article in English | MEDLINE | ID: mdl-27768896

ABSTRACT

Expansion of a hexanucleotide repeat GGGGCC (G4C2) in C9ORF72 is the most common cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). Transcripts carrying (G4C2) expansions undergo unconventional, non-ATG-dependent translation, generating toxic dipeptide repeat (DPR) proteins thought to contribute to disease. Here, we identify the interactome of all DPRs and find that arginine-containing DPRs, polyGly-Arg (GR) and polyPro-Arg (PR), interact with RNA-binding proteins and proteins with low complexity sequence domains (LCDs) that often mediate the assembly of membrane-less organelles. Indeed, most GR/PR interactors are components of membrane-less organelles such as nucleoli, the nuclear pore complex and stress granules. Genetic analysis in Drosophila demonstrated the functional relevance of these interactions to DPR toxicity. Furthermore, we show that GR and PR altered phase separation of LCD-containing proteins, insinuating into their liquid assemblies and changing their material properties, resulting in perturbed dynamics and/or functions of multiple membrane-less organelles.


Subject(s)
Amyotrophic Lateral Sclerosis/metabolism , Dipeptides/metabolism , Frontotemporal Dementia/metabolism , Proteins/metabolism , RNA-Binding Proteins/metabolism , Amyotrophic Lateral Sclerosis/genetics , Animals , C9orf72 Protein , Cell Nucleolus/metabolism , Cytoplasmic Granules/metabolism , DNA Repeat Expansion , Dipeptides/genetics , Drosophila melanogaster/genetics , Frontotemporal Dementia/genetics , Humans , Intracellular Membranes/metabolism , Nuclear Pore/metabolism , Peptides/genetics , Peptides/metabolism , Proteins/genetics
3.
Nature ; 621(7977): 112-119, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37648850

ABSTRACT

Several coastal ecosystems-most notably mangroves and tidal marshes-exhibit biogenic feedbacks that are facilitating adjustment to relative sea-level rise (RSLR), including the sequestration of carbon and the trapping of mineral sediment1. The stability of reef-top habitats under RSLR is similarly linked to reef-derived sediment accumulation and the vertical accretion of protective coral reefs2. The persistence of these ecosystems under high rates of RSLR is contested3. Here we show that the probability of vertical adjustment to RSLR inferred from palaeo-stratigraphic observations aligns with contemporary in situ survey measurements. A deficit between tidal marsh and mangrove adjustment and RSLR is likely at 4 mm yr-1 and highly likely at 7 mm yr-1 of RSLR. As rates of RSLR exceed 7 mm yr-1, the probability that reef islands destabilize through increased shoreline erosion and wave over-topping increases. Increased global warming from 1.5 °C to 2.0 °C would double the area of mapped tidal marsh exposed to 4 mm yr-1 of RSLR by between 2080 and 2100. With 3 °C of warming, nearly all the world's mangrove forests and coral reef islands and almost 40% of mapped tidal marshes are estimated to be exposed to RSLR of at least 7 mm yr-1. Meeting the Paris agreement targets would minimize disruption to coastal ecosystems.


Subject(s)
Global Warming , Temperature , Wetlands , Avicennia/physiology , Carbon Sequestration , Coral Reefs , Global Warming/prevention & control , Global Warming/statistics & numerical data , Animals
4.
Mol Cell ; 74(4): 742-757.e8, 2019 05 16.
Article in English | MEDLINE | ID: mdl-30979586

ABSTRACT

Disturbances in autophagy and stress granule dynamics have been implicated as potential mechanisms underlying inclusion body myopathy (IBM) and related disorders. Yet the roles of core autophagy proteins in IBM and stress granule dynamics remain poorly characterized. Here, we demonstrate that disrupted expression of the core autophagy proteins ULK1 and ULK2 in mice causes a vacuolar myopathy with ubiquitin and TDP-43-positive inclusions; this myopathy is similar to that caused by VCP/p97 mutations, the most common cause of familial IBM. Mechanistically, we show that ULK1/2 localize to stress granules and phosphorylate VCP, thereby increasing VCP's activity and ability to disassemble stress granules. These data suggest that VCP dysregulation and defective stress granule disassembly contribute to IBM-like disease in Ulk1/2-deficient mice. In addition, stress granule disassembly is accelerated by an ULK1/2 agonist, suggesting ULK1/2 as targets for exploiting the higher-order regulation of stress granules for therapeutic intervention of IBM and related disorders.


Subject(s)
Autophagy-Related Protein-1 Homolog/genetics , Lysosomal Storage Diseases/genetics , Muscular Diseases/genetics , Protein Serine-Threonine Kinases/genetics , Valosin Containing Protein/genetics , Adenosine Triphosphatases/genetics , Animals , Autophagy/genetics , DNA-Binding Proteins/genetics , Disease Models, Animal , Humans , Inclusion Bodies/genetics , Inclusion Bodies/pathology , Lysosomal Storage Diseases/metabolism , Lysosomal Storage Diseases/pathology , Mice , Muscular Diseases/metabolism , Muscular Diseases/pathology , Phosphorylation/genetics , Stress, Physiological/genetics , Ubiquitin/genetics
5.
Immunity ; 46(3): 488-503, 2017 03 21.
Article in English | MEDLINE | ID: mdl-28285833

ABSTRACT

The molecular circuits by which antigens activate quiescent T cells remain poorly understood. We combined temporal profiling of the whole proteome and phosphoproteome via multiplexed isobaric labeling proteomics technology, computational pipelines for integrating multi-omics datasets, and functional perturbation to systemically reconstruct regulatory networks underlying T cell activation. T cell receptors activated the T cell proteome and phosphoproteome with discrete kinetics, marked by early dynamics of phosphorylation and delayed ribosome biogenesis and mitochondrial activation. Systems biology analyses identified multiple functional modules, active kinases, transcription factors and connectivity between them, and mitochondrial pathways including mitoribosomes and complex IV. Genetic perturbation revealed physiological roles for mitochondrial enzyme COX10-mediated oxidative phosphorylation in T cell quiescence exit. Our multi-layer proteomics profiling, integrative network analysis, and functional studies define landscapes of the T cell proteome and phosphoproteome and reveal signaling and bioenergetics pathways that mediate lymphocyte exit from quiescence.


Subject(s)
Lymphocyte Activation/immunology , Signal Transduction/immunology , T-Lymphocytes/immunology , Alkyl and Aryl Transferases/immunology , Animals , Energy Metabolism , Mass Spectrometry , Membrane Proteins/immunology , Mice , Mice, Inbred C57BL , Phosphorylation , Proteomics , Receptors, Antigen, T-Cell/immunology
6.
Bioinformatics ; 2024 Oct 03.
Article in English | MEDLINE | ID: mdl-39360977

ABSTRACT

MOTIVATION: Integrative analysis of heterogeneous expression data remains challenging due to variations in platform, RNA quality, sample processing, and other unknown technical effects. Selecting the approach for removing unwanted batch effects can be a time-consuming and tedious process, especially for more biologically focused investigators. RESULTS: Here, we present BatchFLEX, a Shiny app that can facilitate visualization and correction of batch effects using several established methods. BatchFLEX can visualize the variance contribution of a factor before and after correction. As an example, we've analyzed ImmGen microarray data and enhanced its expression signals that distinguishes each immune cell type. Moreover, our analysis revealed the impact of the batch correction in altering the gene expression rank and single-sample GSEA pathway scores in immune cell types, highlighting the importance of real-time assessment of the batch correction for optimal downstream analysis. AVAILABILITY: Our tool is available through Github https://github.com/shawlab-moffitt/BATCH-FLEX-ShinyApp with an online example on Shiny.io https://shawlab-moffitt.shinyapps.io/batch_flex/. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.

7.
PLoS Comput Biol ; 20(2): e1011873, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38335222

ABSTRACT

Super enhancers (SE), large genomic elements that activate transcription and drive cell identity, have been found with cancer-specific gene regulation in human cancers. Recent studies reported the importance of understanding the cooperation and function of SE internal components, i.e., the constituent enhancers (CE). However, there are no pan-cancer studies to identify cancer-specific SE signatures at the constituent level. Here, by revisiting pan-cancer SE activities with H3K27Ac ChIP-seq datasets, we report fingerprint SE signatures for 28 cancer types in the NCI-60 cell panel. We implement a mixture model to discriminate active CEs from inactive CEs by taking into consideration ChIP-seq variabilities between cancer samples and across CEs. We demonstrate that the model-based estimation of CE states provides improved functional interpretation of SE-associated regulation. We identify cancer-specific CEs by balancing their active prevalence with their capability of encoding cancer type identities. We further demonstrate that cancer-specific CEs have the strongest per-base enhancer activities in independent enhancer sequencing assays, suggesting their importance in understanding critical SE signatures. We summarize fingerprint SEs based on the cancer-specific statuses of their component CEs and build an easy-to-use R package to facilitate the query, exploration, and visualization of fingerprint SEs across cancers.


Subject(s)
Neoplasms , Super Enhancers , Humans , Epigenomics , Enhancer Elements, Genetic/genetics , Gene Expression Regulation , Neoplasms/genetics
8.
Thorax ; 79(8): 778-787, 2024 Jul 16.
Article in English | MEDLINE | ID: mdl-38508718

ABSTRACT

INTRODUCTION: Novel therapeutic strategies are urgently needed for Mycobacterium avium complex pulmonary disease (MAC-PD). Human mesenchymal stromal cells (MSCs) can directly inhibit MAC growth, but their effect on intracellular bacilli is unknown. We investigated the ability of human MSCs to reduce bacterial replication and inflammation in MAC-infected macrophages and in a murine model of MAC-PD. METHODS: Human monocyte-derived macrophages (MDMs) were infected with M. avium Chester strain and treated with human bone marrow-derived MSCs. Intracellular and extracellular colony-forming units (CFUs) were counted at 72 hours. Six-week-old female balb/c mice were infected by nebulisation of M. avium Chester. Mice were treated with 1×106 intravenous human MSCs or saline control at 21 and 28 days post-infection. Lungs, liver and spleen were harvested 42 days post-infection for bacterial counts. Cytokines were quantified by ELISA. RESULTS: MSCs reduced intracellular bacteria in MDMs over 72 hours (median 35% reduction, p=0.027). MSC treatment increased extracellular concentrations of prostaglandin E2 (PGE2) (median 10.1-fold rise, p=0.002) and reduced tumour necrosis factor-α (median 28% reduction, p=0.025). Blocking MSC PGE2 production by cyclo-oxygenase-2 (COX-2) inhibition with celecoxib abrogated the antimicrobial effect, while this was restored by adding exogenous PGE2. MSC-treated mice had lower pulmonary CFUs (median 18% reduction, p=0.012), but no significant change in spleen or liver CFUs compared with controls. CONCLUSION: MSCs can modulate inflammation and reduce intracellular M. avium growth in human macrophages via COX-2/PGE2 signalling and inhibit pulmonary bacterial replication in a murine model of chronic MAC-PD.


Subject(s)
Disease Models, Animal , Mesenchymal Stem Cells , Mice, Inbred BALB C , Mycobacterium avium-intracellulare Infection , Animals , Mice , Female , Humans , Mycobacterium avium-intracellulare Infection/microbiology , Mycobacterium avium Complex , Mesenchymal Stem Cell Transplantation/methods , Macrophages/microbiology , Dinoprostone/metabolism , Sulfonamides/pharmacology , Mycobacterium avium
9.
Mol Cell ; 62(4): 491-506, 2016 05 19.
Article in English | MEDLINE | ID: mdl-27203176

ABSTRACT

ULK1 and ULK2 are thought to be essential for initiating autophagy, and Ulk1/2-deficient mice die perinatally of autophagy-related defects. Therefore, we used a conditional knockout approach to investigate the roles of ULK1/2 in the brain. Although the mice showed neuronal degeneration, the neurons showed no accumulation of P62(+)/ubiquitin(+) inclusions or abnormal membranous structures, which are observed in mice lacking other autophagy genes. Rather, neuronal death was associated with activation of the unfolded protein response (UPR) pathway. An unbiased proteomics approach identified SEC16A as an ULK1/2 interaction partner. ULK-mediated phosphorylation of SEC16A regulated the assembly of endoplasmic reticulum (ER) exit sites and ER-to-Golgi trafficking of specific cargo, and did not require other autophagy proteins (e.g., ATG13). The defect in ER-to-Golgi trafficking activated the UPR pathway in ULK-deficient cells; both processes were reversed upon expression of SEC16A with a phosphomimetic substitution. Thus, the regulation of ER-to-Golgi trafficking by ULK1/2 is essential for cellular homeostasis.


Subject(s)
Autophagy-Related Protein-1 Homolog/metabolism , Brain/enzymology , Endoplasmic Reticulum/enzymology , Fibroblasts/enzymology , Golgi Apparatus/enzymology , Protein Serine-Threonine Kinases/metabolism , Animals , Autophagy , Autophagy-Related Protein 7/genetics , Autophagy-Related Protein 7/metabolism , Autophagy-Related Protein-1 Homolog/deficiency , Autophagy-Related Protein-1 Homolog/genetics , Brain/pathology , COP-Coated Vesicles/enzymology , Caenorhabditis elegans/enzymology , Caenorhabditis elegans/genetics , Caenorhabditis elegans Proteins/metabolism , Carrier Proteins/genetics , Carrier Proteins/metabolism , Endoplasmic Reticulum/pathology , Female , Genotype , Golgi Apparatus/pathology , HEK293 Cells , Homeostasis , Humans , Male , Mice, 129 Strain , Mice, Inbred C57BL , Mice, Knockout , Nerve Degeneration , Nuclear Proteins/genetics , Nuclear Proteins/metabolism , Phenotype , Phosphorylation , Protein Serine-Threonine Kinases/deficiency , Protein Serine-Threonine Kinases/genetics , Protein Transport , RNA Interference , Time Factors , Transfection , Unfolded Protein Response , Vesicular Transport Proteins/genetics , Vesicular Transport Proteins/metabolism
10.
Nucleic Acids Res ; 50(6): 3115-3127, 2022 04 08.
Article in English | MEDLINE | ID: mdl-35234924

ABSTRACT

Super enhancers (SEs) are broad enhancer domains usually containing multiple constituent enhancers that hold elevated activities in gene regulation. Disruption in one or more constituent enhancers causes aberrant SE activities that lead to gene dysregulation in diseases. To quantify SE aberrations, differential analysis is performed to compare SE activities between cell conditions. The state-of-art strategy in estimating differential SEs relies on overall activities and neglect the changes in length and structure of SEs. Here, we propose a novel computational method to identify differential SEs by weighting the combinatorial effects of constituent-enhancer activities and locations (i.e. internal dynamics). In addition to overall activity changes, our method identified four novel classes of differential SEs with distinct enhancer structural alterations. We demonstrate that these structure alterations hold distinct regulatory impact, such as regulating different number of genes and modulating gene expression with different strengths, highlighting the differentiated regulatory roles of these unexplored SE features. When compared to the existing method, our method showed improved identification of differential SEs that were linked to better discernment of cell-type-specific SE activity and functional interpretation.


Subject(s)
Enhancer Elements, Genetic , Gene Expression Regulation , Cell Differentiation
11.
Proc Natl Acad Sci U S A ; 118(40)2021 10 05.
Article in English | MEDLINE | ID: mdl-34593633

ABSTRACT

Historically, the production of reactive oxygen species (ROS) in the ocean has been attributed to photochemical and biochemical reactions. However, hydrothermal vents emit globally significant inventories of reduced Fe and S species that should react rapidly with oxygen in bottom water and serve as a heretofore unmeasured source of ROS. Here, we show that the Fe-catalyzed oxidation of reduced sulfur species in hydrothermal vent plumes in the deep oceans supported the abiotic formation of ROS at concentrations 20 to 100 times higher than the average for photoproduced ROS in surface waters. ROS (measured as hydrogen peroxide) were determined in hydrothermal plumes and seeps during a series of Alvin dives at the North East Pacific Rise. Hydrogen peroxide inventories in emerging plumes were maintained at levels proportional to the oxygen introduced by mixing with bottom water. Fenton chemistry predicts the production of hydroxyl radical under plume conditions through the reaction of hydrogen peroxide with the abundant reduced Fe in hydrothermal plumes. A model of the hydroxyl radical fate under plume conditions supports the role of plume ROS in the alteration of refractory organic molecules in seawater. The ocean's volume circulates through hydrothermal plumes on timescales similar to the age of refractory dissolved organic carbon. Thus, plume-generated ROS can initiate reactions that may affect global ocean carbon inventories.

12.
BMC Bioinformatics ; 24(1): 266, 2023 Jun 28.
Article in English | MEDLINE | ID: mdl-37380943

ABSTRACT

Pathway-level survival analysis offers the opportunity to examine molecular pathways and immune signatures that influence patient outcomes. However, available survival analysis algorithms are limited in pathway-level function and lack a streamlined analytical process. Here we present a comprehensive pathway-level survival analysis suite, PATH-SURVEYOR, which includes a Shiny user interface with extensive features for systematic exploration of pathways and covariates in a Cox proportional-hazard model. Moreover, our framework offers an integrative strategy for performing Hazard Ratio ranked Gene Set Enrichment Analysis and pathway clustering. As an example, we applied our tool in a combined cohort of melanoma patients treated with checkpoint inhibition (ICI) and identified several immune populations and biomarkers predictive of ICI efficacy. We also analyzed gene expression data of pediatric acute myeloid leukemia (AML) and performed an inverse association of drug targets with the patient's clinical endpoint. Our analysis derived several drug targets in high-risk KMT2A-fusion-positive patients, which were then validated in AML cell lines in the Genomics of Drug Sensitivity database. Altogether, the tool offers a comprehensive suite for pathway-level survival analysis and a user interface for exploring drug targets, molecular features, and immune populations at different resolutions.


Subject(s)
Leukemia, Myeloid, Acute , Melanoma , Child , Humans , Drug Repositioning , Medical Oncology , Melanoma/drug therapy , Melanoma/genetics , Algorithms , Leukemia, Myeloid, Acute/drug therapy , Leukemia, Myeloid, Acute/genetics
13.
Heart Lung Circ ; 32(10): 1141-1147, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37758637

ABSTRACT

The Australian Cardiovascular Alliance (ACvA), the Cardiac Society of Australia and New Zealand (CSANZ) and the National Heart Foundation of Australia (NHFA) recently joined forces to bring the cardiovascular and stroke community together to convene and document a national discussion and propose a national CVD Implementation and Policy agenda and action plan. This includes prevention and screening, acute care and secondary prevention.


Subject(s)
Cardiovascular Diseases , Humans , Cardiovascular Diseases/epidemiology , Cardiovascular Diseases/prevention & control , Australia/epidemiology , Policy , New Zealand/epidemiology
14.
Clin Microbiol Rev ; 34(4): e0006421, 2021 12 15.
Article in English | MEDLINE | ID: mdl-34612662

ABSTRACT

There is an urgent need for new antimicrobial strategies for treating complex infections and emerging pathogens. Human mesenchymal stromal cells (MSCs) are adult multipotent cells with antimicrobial properties, mediated through direct bactericidal activity and modulation of host innate and adaptive immune cells. More than 30 in vivo studies have reported on the use of human MSCs for the treatment of infectious diseases, with many more studies of animal MSCs in same-species models of infection. MSCs demonstrate potent antimicrobial effects against the major classes of human pathogens (bacteria, viruses, fungi, and parasites) across a wide range of infection models. Mechanistic studies have yielded important insight into their immunomodulatory and bactericidal activity, which can be enhanced through various forms of preconditioning. MSCs are being investigated in over 80 clinical trials for difficult-to-treat infectious diseases, including sepsis and pulmonary, intra-abdominal, cutaneous, and viral infections. Completed trials consistently report MSCs to be safe and well tolerated, with signals of efficacy against some infectious diseases. Although significant obstacles must be overcome to produce a standardized, affordable, clinical-grade cell therapy, these studies suggest that MSCs may have particular potential as an adjunct therapy in complex or resistant infections.


Subject(s)
Communicable Diseases , Mesenchymal Stem Cell Transplantation , Mesenchymal Stem Cells , Animals , Anti-Bacterial Agents , Communicable Diseases/drug therapy , Humans , Immunomodulation
15.
BMC Cancer ; 21(1): 1233, 2021 Nov 17.
Article in English | MEDLINE | ID: mdl-34789196

ABSTRACT

BACKGROUND: RNA editing leads to post-transcriptional variation in protein sequences and has important biological implications. We sought to elucidate the landscape of RNA editing events across pediatric cancers. METHODS: Using RNA-Seq data mapped by a pipeline designed to minimize mapping ambiguity, we investigated RNA editing in 711 pediatric cancers from the St. Jude/Washington University Pediatric Cancer Genome Project focusing on coding variants which can potentially increase protein sequence diversity. We combined de novo detection using paired tumor DNA-RNA data with analysis of known RNA editing sites. RESULTS: We identified 722 unique RNA editing sites in coding regions across pediatric cancers, 70% of which were nonsynonymous recoding variants. Nearly all editing sites represented the canonical A-to-I (n = 706) or C-to-U sites (n = 14). RNA editing was enriched in brain tumors compared to other cancers, including editing of glutamate receptors and ion channels involved in neurotransmitter signaling. RNA editing profiles of each pediatric cancer subtype resembled those of the corresponding normal tissue profiled by the Genotype-Tissue Expression (GTEx) project. CONCLUSIONS: In this first comprehensive analysis of RNA editing events in pediatric cancer, we found that the RNA editing profile of each cancer subtype is similar to its normal tissue of origin. Tumor-specific RNA editing events were not identified indicating that successful immunotherapeutic targeting of RNA-edited peptides in pediatric cancer should rely on increased antigen presentation on tumor cells compared to normal but not on tumor-specific RNA editing per se.


Subject(s)
Neoplasms/genetics , RNA Editing , Sequence Analysis, RNA/methods , Brain Neoplasms/genetics , Child , DNA, Neoplasm , Humans , Immunotherapy , Neoplasms/metabolism , Neoplasms/therapy , Open Reading Frames , Organ Specificity , RNA, Neoplasm , Whole Genome Sequencing
16.
Br J Neurosurg ; : 1-6, 2021 Dec 20.
Article in English | MEDLINE | ID: mdl-34927521

ABSTRACT

Background: Optimal management of intracranial infections relies on microbiological diagnosis and antimicrobial choice, but conventional culture-based testing is limited by pathogen viability and pre-sampling antimicrobial exposure. Broad-range 16S rRNA gene sequencing has been reported in the management of culture-negative infections but its utility in intracranial infection is not well-described. We studied the efficacy of 16S rRNA gene sequencing to inform microbiological diagnosis and antimicrobial choice in intracranial infections.Methods: This was a retrospective study of all intraoperative neurosurgical specimens sent for 16S rRNA gene sequencing over an 8-year period at a regional neurosurgical centre in the UK. Specimen selection was performed using multidisciplinary approach, combining neurosurgical and infection specialist discussion.Results: Twenty-five intraoperative specimens taken during neurosurgery from 24 patients were included in the study period. The most common reason for referral was pre-sampling antimicrobial exposure (68%). Bacterial rDNA was detected in 60% of specimens. 16S rRNA gene sequencing contributed to microbiological diagnosis in 15 patients and informed antimicrobial management in 10 of 24 patients with intracranial infection. These included targeted antibiotics after detection of a clinically-significant pathogen that had not been identified through other microbiological testing (3 cases), detection of commensal organisms in neurosurgical infection which justified continued broad cover (2 cases) and negative results from intracranial lesions with low clinical suspicion of bacterial infection which justified avoidance or cessation of antibiotics (5 cases).Conclusion: Overall, 16S rRNA gene sequencing represented an incremental improvement in diagnostic testing and was most appropriately used to complement, rather than replace, conventional culture-based testing for intracranial infection.

17.
RNA ; 24(8): 1056-1066, 2018 08.
Article in English | MEDLINE | ID: mdl-29844105

ABSTRACT

The recent identification of compounds that interact with the spliceosome (sudemycins, spliceostatin A, and meayamycin) indicates that these molecules modulate aberrant splicing via SF3B1 inhibition. Through whole transcriptome sequencing, we have demonstrated that treatment of Rh18 cells with sudemycin leads to exon skipping as the predominant aberrant splicing event. This was also observed following reanalysis of published RNA-seq data sets derived from HeLa cells after spliceostatin A exposure. These results are in contrast to previous reports that indicate that intron retention was the major consequence of SF3B1 inhibition. Analysis of the exon junctions up-regulated by these small molecules indicated that these sequences were absent in annotated human genes, suggesting that aberrant splicing events yielded novel RNA transcripts. Interestingly, the length of preferred downstream exons was significantly longer than the skipped exons, although there was no difference between the lengths of introns flanking skipped exons. The reading frame of the aberrantly skipped exons maintained a ratio of 2:1:1, close to that of the cassette exons (3:1:1) present in naturally occurring isoforms, suggesting negative selection by the nonsense-mediated decay (NMD) machinery for out-of-frame transcripts. Accordingly, genes involved in NMD and RNAs encoding proteins involved in the splicing process were enriched in both data sets. Our findings, therefore, further elucidate the mechanisms by which SF3B1 inhibition modulates pre-mRNA splicing.


Subject(s)
Epoxy Compounds/pharmacology , Exons/genetics , Phosphoproteins/antagonists & inhibitors , Phosphoproteins/genetics , Protein Biosynthesis/genetics , RNA Splicing Factors/antagonists & inhibitors , RNA Splicing Factors/genetics , RNA Splicing/genetics , Spiro Compounds/pharmacology , Spliceosomes/genetics , Base Sequence , Cell Line, Tumor , HCT116 Cells , HeLa Cells , Humans , Nonsense Mediated mRNA Decay/genetics , RNA Interference , RNA, Messenger/genetics , RNA, Small Interfering/genetics , Reading Frames/genetics , Sequence Analysis, RNA , Transcriptome/genetics
18.
Acta Neuropathol ; 137(4): 637-655, 2019 04.
Article in English | MEDLINE | ID: mdl-30770999

ABSTRACT

Histone H3 K27M mutation is the defining molecular feature of the devastating pediatric brain tumor, diffuse intrinsic pontine glioma (DIPG). The prevalence of histone H3 K27M mutations indicates a critical role in DIPGs, but the contribution of the mutation to disease pathogenesis remains unclear. We show that knockdown of this mutation in DIPG xenografts restores K27M-dependent loss of H3K27me3 and delays tumor growth. Comparisons of matched DIPG xenografts with and without K27M knockdown allowed identification of mutation-specific effects on the transcriptome and epigenome. The resulting transcriptional changes recapitulate expression signatures from K27M primary DIPG tumors and are strongly enriched for genes associated with nervous system development. Integrated analysis of ChIP-seq and expression data showed that genes upregulated by the mutation are overrepresented in apparently bivalent promoters. Many of these targets are associated with more immature differentiation states. Expression profiles indicate K27M knockdown decreases proliferation and increases differentiation within lineages represented in DIPG. These data suggest that K27M-mediated loss of H3K27me3 directly regulates a subset of genes by releasing poised promoters, and contributes to tumor phenotype and growth by limiting differentiation. The delayed tumor growth associated with knockdown of H3 K27M provides evidence that this highly recurrent mutation is a relevant therapeutic target.


Subject(s)
Brain Stem Neoplasms/genetics , Cell Differentiation/genetics , Diffuse Intrinsic Pontine Glioma/genetics , Histones/genetics , Mutation , Animals , Brain Stem Neoplasms/pathology , Cell Line, Tumor , Diffuse Intrinsic Pontine Glioma/pathology , Disease Models, Animal , Gene Knockdown Techniques , Mice
20.
Expert Opin Emerg Drugs ; 24(1): 29-41, 2019 03.
Article in English | MEDLINE | ID: mdl-30841764

ABSTRACT

INTRODUCTION: The acute respiratory distress syndrome (ARDS) is a common and catastrophic condition, with a high mortality rate and economic burden on society. Despite 50 years of study, there is no specific pharmacological therapy for ARDS. Areas covered: This review outlines the definitions, epidemiology, risk factors and pathophysiology of ARDS. The priority of developing a clinically-relevant model for ARDS to test pre-clinical candidates is discussed, together with the limitations of current models. The scientific rationale of emerging therapeutic candidates is outlined in the setting of the biological mechanisms implicated in the complex pathogenesis of ARDS. Emerging therapies, currently in clinical trials, are discussed, including the pre-clinical basis for their use and the expected timeline to trial completion. Expert opinion: We highlight the necessity of improving pre-clinical models of ARDS and the design of clinical trials for the development of novel pharmacological therapies. We reflect on the most promising emerging strategies and their potential role in ARDS management.


Subject(s)
Drug Development/methods , Drug Evaluation, Preclinical/methods , Respiratory Distress Syndrome/drug therapy , Animals , Clinical Trials as Topic/methods , Cost of Illness , Humans , Research Design , Respiratory Distress Syndrome/mortality , Respiratory Distress Syndrome/physiopathology , Risk Factors
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