1,250 research outputs found
Vector-pathogen interactions within the vector, Culicoides sonorensis
Doctor of PhilosophyDivision of BiologyKristin MichelThe biting midge, Culicoides sonorensis, vectors orbiviruses of economic importance, such as epizootic hemorrhagic disease virus (EHDV). Due to the limitations in available molecular tools, critical Culicoides-orbivirus interactions underlying vector competence remain unclear. To provide a foundation for the study of midge-EHDV interactions, RNA interference (RNAi) was developed as a reverse genetic tool, and EHDV-2 infection dynamics were determined within C. sonorensis. To develop RNAi, exogenous double-stranded RNA (dsRNA) was injected into C. sonorensis adults specific to the C. sonorensis inhibitor of apoptosis protein 1 (CsIAP1) ortholog (dsCsIAP1). A significant decrease in CsIAP1 transcripts was observed in whole midges, with highest reduction in the midgut. In addition, dsCsIAP1-injected midges had increased mortality, a loss of midgut tissue integrity, and increased caspase activity. The longevity and midgut phenotypes were partially reversed by the co-injection of dsRNA specific to the C. sonorensis initiator caspase Dronc ortholog and CsIAP1. These results demonstrated that RNAi can be achieved in the midge midgut through injection of target dsRNAs into the hemolymph. Furthermore, the time course of EHDV-2 infection within C. sonorensis was characterized. EHDV-2 infection was observed in the midgut and secondary tissues, including the salivary glands, by 5 days post-feeding (dpf). These data are consistent with dissemination of EHDV-2 to secondary susceptible tissues throughout the midge via the hemolymph and indicate that virus transmission by C. sonorensis may occur as early as 5 dpf. This work provides a foundation for the future study of Culicoides-orbivirus interactions, including the antiviral role of RNAi at the midgut barrier
Efficacy of the Enquiring About Tolerance (EAT) study among infants at high risk of developing food allergy.
BACKGROUND: The Enquiring About Tolerance (EAT) study was a randomized trial of the early introduction of allergenic solids into the infant diet from 3 months of age. The intervention effect did not reach statistical significance in the intention-to-treat analysis of the primary outcome. OBJECTIVE: We sought to determine whether infants at high risk of developing a food allergy benefited from early introduction. METHODS: A secondary intention-to-treat analysis was performed of 3 groups: nonwhite infants; infants with visible eczema at enrollment, with severity determined by SCORAD; and infants with enrollment food sensitization (specific IgE ≥0.1 kU/L). RESULTS: Among infants with sensitization to 1 or more foods at enrollment (≥0.1 kU/L), early introduction group (EIG) infants developed significantly less food allergy to 1 or more foods than standard introduction group (SIG) infants (SIG, 34.2%; EIG, 19.2%; P = .03), and among infants with sensitization to egg at enrollment, EIG infants developed less egg allergy (SIG, 48.6%; EIG, 20.0%; P = .01). Similarly, among infants with moderate SCORAD (15-<40) at enrollment, EIG infants developed significantly less food allergy to 1 or more foods (SIG, 46.7%; EIG, 22.6%; P = .048) and less egg allergy (SIG, 43.3%; EIG, 16.1%; P = .02). CONCLUSION: Early introduction was effective in preventing the development of food allergy in specific groups of infants at high risk of developing food allergy: those sensitized to egg or to any food at enrollment and those with eczema of increasing severity at enrollment. This efficacy occurred despite low adherence to the early introduction regimen. This has significant implications for the new national infant feeding recommendations that are emerging around the world
The RESPECT Study for consensus on global bereavement care after stillbirth.
OBJECTIVE: To develop global consensus on a set of evidence-based core principles for bereavement care after stillbirth. METHODS: A modified policy-Delphi methodology was used to consult international stakeholders and healthcare workers with experience in stillbirth between September 2017 and October 2018. Five sequential rounds involved two expert stakeholder meetings and three internet-based surveys, including a global internet-based survey targeted at healthcare workers in a wide range of settings. RESULTS: Initially, 23 expert stakeholders considered 43 evidence-based themes derived from systematic reviews, identifying 10 core principles. The global survey received 236 responses from participants in 26 countries, after which nine principles met a priori criteria for inclusion. The final stakeholder meeting and internet-based survey of all participants confirmed consensus on eight core principles. Highest quality bereavement care should be enabled through training of healthcare staff to reduce stigma and establish respectful care, including acknowledgement and support for grief responses, and provision for physical and psychologic needs. Women and families should be supported to make informed choices, including those concerning their future reproductive health. CONCLUSION: Consensus was established for eight principles for stillbirth bereavement care. Further work should explore implementation and involve the voices of women and families globally
Genomic, Pathway Network, and Immunologic Features Distinguishing Squamous Carcinomas
This integrated, multiplatform PanCancer Atlas study co-mapped and identified distinguishing
molecular features of squamous cell carcinomas (SCCs) from five sites associated with smokin
Pan-Cancer Analysis of lncRNA Regulation Supports Their Targeting of Cancer Genes in Each Tumor Context
Long noncoding RNAs (lncRNAs) are commonly dys-regulated in tumors, but only a handful are known toplay pathophysiological roles in cancer. We inferredlncRNAs that dysregulate cancer pathways, onco-genes, and tumor suppressors (cancer genes) bymodeling their effects on the activity of transcriptionfactors, RNA-binding proteins, and microRNAs in5,185 TCGA tumors and 1,019 ENCODE assays.Our predictions included hundreds of candidateonco- and tumor-suppressor lncRNAs (cancerlncRNAs) whose somatic alterations account for thedysregulation of dozens of cancer genes and path-ways in each of 14 tumor contexts. To demonstrateproof of concept, we showed that perturbations tar-geting OIP5-AS1 (an inferred tumor suppressor) andTUG1 and WT1-AS (inferred onco-lncRNAs) dysre-gulated cancer genes and altered proliferation ofbreast and gynecologic cancer cells. Our analysis in-dicates that, although most lncRNAs are dysregu-lated in a tumor-specific manner, some, includingOIP5-AS1, TUG1, NEAT1, MEG3, and TSIX, synergis-tically dysregulate cancer pathways in multiple tumorcontexts
Pan-cancer Alterations of the MYC Oncogene and Its Proximal Network across the Cancer Genome Atlas
Although theMYConcogene has been implicated incancer, a systematic assessment of alterations ofMYC, related transcription factors, and co-regulatoryproteins, forming the proximal MYC network (PMN),across human cancers is lacking. Using computa-tional approaches, we define genomic and proteo-mic features associated with MYC and the PMNacross the 33 cancers of The Cancer Genome Atlas.Pan-cancer, 28% of all samples had at least one ofthe MYC paralogs amplified. In contrast, the MYCantagonists MGA and MNT were the most frequentlymutated or deleted members, proposing a roleas tumor suppressors.MYCalterations were mutu-ally exclusive withPIK3CA,PTEN,APC,orBRAFalterations, suggesting that MYC is a distinct onco-genic driver. Expression analysis revealed MYC-associated pathways in tumor subtypes, such asimmune response and growth factor signaling; chro-matin, translation, and DNA replication/repair wereconserved pan-cancer. This analysis reveals insightsinto MYC biology and is a reference for biomarkersand therapeutics for cancers with alterations ofMYC or the PMN
Spatial Organization and Molecular Correlation of Tumor-Infiltrating Lymphocytes Using Deep Learning on Pathology Images
Beyond sample curation and basic pathologic characterization, the digitized H&E-stained images
of TCGA samples remain underutilized. To highlight this resource, we present mappings of tumorinfiltrating lymphocytes (TILs) based on H&E images from 13 TCGA tumor types. These TIL
maps are derived through computational staining using a convolutional neural network trained to
classify patches of images. Affinity propagation revealed local spatial structure in TIL patterns and
correlation with overall survival. TIL map structural patterns were grouped using standard
histopathological parameters. These patterns are enriched in particular T cell subpopulations
derived from molecular measures. TIL densities and spatial structure were differentially enriched
among tumor types, immune subtypes, and tumor molecular subtypes, implying that spatial
infiltrate state could reflect particular tumor cell aberration states. Obtaining spatial lymphocytic
patterns linked to the rich genomic characterization of TCGA samples demonstrates one use for
the TCGA image archives with insights into the tumor-immune microenvironment
Whole-exome sequencing combined with functional genomics reveals novel candidate driver cancer genes in endometrial cancer
Endometrial cancer is the most common gynecological malignancy, with more than 280,000 cases occurring annually worldwide. Although previous studies have identified important common somatic mutations in endometrial cancer, they have primarily focused on a small set of known cancer genes and have thus provided a limited view of the molecular basis underlying this disease. Here we have developed an integrated systems-biology approach to identifying novel cancer genes contributing to endometrial tumorigenesis. We first performed whole-exome sequencing on 13 endometrial cancers and matched normal samples, systematically identifying somatic alterations with high precision and sensitivity. We then combined bioinformatics prioritization with high-throughput screening (including both shRNA-mediated knockdown and expression of wild-type and mutant constructs) in a highly sensitive cell viability assay. Our results revealed 12 potential driver cancer genes including 10 tumor-suppressor candidates (ARID1A, INHBA, KMO, TTLL5, GRM8, IGFBP3, AKTIP, PHKA2, TRPS1, and WNT11) and two oncogene candidates (ERBB3 and RPS6KC1). The results in the ''sensor'' cell line were recapitulated by siRNA-mediated knockdown in endometrial cancer cell lines. Focusing on ARID1A, we integrated mutation profiles with functional proteomics in 222 endometrial cancer samples, demonstrating that ARID1A mutations frequently co-occur with mutations in the phosphatidylinositol 3-kinase (PI3K) pathway and are associated with PI3K pathway activation. siRNA knockdown in endometrial cancer cell lines increased AKT phosphorylation supporting ARID1A as a novel regulator of PI3K pathway activity. Our study presents the first unbiased view of somatic coding mutations in endometrial cancer and provides functional evidence for diverse driver genes and mutations in this disease. © 2012, Published by Cold Spring Harbor Laboratory Press.Link_to_subscribed_fulltex
Comprehensive Molecular Characterization of Pheochromocytoma and Paraganglioma
SummaryWe report a comprehensive molecular characterization of pheochromocytomas and paragangliomas (PCCs/PGLs), a rare tumor type. Multi-platform integration revealed that PCCs/PGLs are driven by diverse alterations affecting multiple genes and pathways. Pathogenic germline mutations occurred in eight PCC/PGL susceptibility genes. We identified CSDE1 as a somatically mutated driver gene, complementing four known drivers (HRAS, RET, EPAS1, and NF1). We also discovered fusion genes in PCCs/PGLs, involving MAML3, BRAF, NGFR, and NF1. Integrated analysis classified PCCs/PGLs into four molecularly defined groups: a kinase signaling subtype, a pseudohypoxia subtype, a Wnt-altered subtype, driven by MAML3 and CSDE1, and a cortical admixture subtype. Correlates of metastatic PCCs/PGLs included the MAML3 fusion gene. This integrated molecular characterization provides a comprehensive foundation for developing PCC/PGL precision medicine
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