539 research outputs found
Characterizing Effects of Pevonedistat in Myeloproliferative Neoplasms
From the Washington University Office of Undergraduate Research Digest (WUURD), Vol. 13, 05-01-2018. Published by the Office of Undergraduate Research. Joy Zalis Kiefer, Director of Undergraduate Research and Associate Dean in the College of Arts & Sciences; Lindsey Paunovich, Editor; Helen Human, Programs Manager and Assistant Dean in the College of Arts and Sciences Mentor(s): Stephanie O
Site-Directed Spin Label EPR Studies of the Interaction Between the Influenza A Proteins (M1 and M2) Involved in Viral Assembly
Influenza A presents a significant concern for public health as it is the cause of seasonal outbreaks and global pandemics. The influenza A proteins, matrix protein 1 (M1) and matrix protein 2 (M2), have been shown to be essential for the propagation of new viruses, especially through their roles in viral assembly and budding. The M2 cytoplasmic tail interacts with the M1 protein, recruiting it to the viral budding site and enabling proper packaging of the viral genome. The Howard lab has previously characterized residues 50-70 in the M2 cytoplasmic tail and the M2 protein’s conformational equilibria by sitedirected spin label electron paramagnetic resonance (SDSL-EPR). This work lays groundwork for the establishment of a system in which to see changes in the M2 protein upon M1 binding. Methods for the overexpression and purification of the M1 protein are presented. Selected M2 sites (43, 57, 68) were studied by SDSL-EPR in the presence of Nterminal M1 (residues 1-165), with M2 sites 43 and 57 acting as indicators of the M2 protein’s conformational dynamics. Binding between M1 and M2 could not be rigorously established, but preliminary results suggest little change in the M2 protein in the presence of the M1 protein
Cellular Origins of EGFR-Driven Lung Cancer Cells Determine Sensitivity to Therapy
Targeting the epidermal growth factor receptor (EGFR) with tyrosine kinase inhibitors (TKIs) is one of the major precision medicine treatment options for lung adenocarcinoma. Due to common development of drug resistance to first- and second-generation TKIs, third-generation inhibitors, including osimertinib and rociletinib, have been developed. A model of EGFR-driven lung cancer and a method to develop tumors of distinct epigenetic states through 3D organotypic cultures are described here. It is discovered that activation of the EGFR T790M/L858R mutation in lung epithelial cells can drive lung cancers with alveolar or bronchiolar features, which can originate from alveolar type 2 (AT2) cells or bronchioalveolar stem cells, but not basal cells or club cells of the trachea. It is also demonstrated that these clones are able to retain their epigenetic differences through passaging orthotopically in mice and crucially that they have distinct drug vulnerabilities. This work serves as a blueprint for exploring how epigenetics can be used to stratify patients for precision medicine decisions
Pevonedistat targets malignant cells in myeloproliferative neoplasms in vitro and in vivo via NFκB pathway inhibition
Targeted inhibitors of JAK2 (eg ruxolitinib) often provide symptomatic relief for myeloproliferative neoplasm (MPN) patients, but the malignant clone persists and remains susceptible to disease transformation. These observations suggest that targeting alternative dysregulated signaling pathways may provide therapeutic benefit. Previous studies identified NFκB pathway hyperactivation in myelofibrosis (MF) and secondary acute myeloid leukemia (sAML) that was insensitive to JAK2 inhibition. Here, we provide evidence that NFκB pathway inhibition via pevonedistat targets malignant cells in MPN patient samples as well as in MPN and patient-derived xenograft mouse models that are nonredundant with ruxolitinib. Colony forming assays revealed preferential inhibition of MF colony growth compared with normal colony formation. In mass cytometry studies, pevonedistat blunted canonical TNFα responses in MF and sAML patient CD34+ cells. Pevonedistat also inhibited hyperproduction of inflammatory cytokines more effectively than ruxolitinib. Upon pevonedistat treatment alone or in combination with ruxolitinib, MPN mouse models exhibited reduced disease burden and improved survival. These studies demonstrating efficacy of pevonedistat in MPN cells in vitro as well as in vivo provide a rationale for therapeutic inhibition of NFκB signaling for MF treatment. Based on these findings, a Phase 1 clinical trial combining pevonedistat with ruxolitinib has been initiated
Transforming LIS Education through Disability Inclusion
Combining perspectives from Australia, Canada, New Zealand, and the US, this
international panel will develop an honest dialog on disability inclusion in LIS education,
drawing on empirical research, discursive analysis, and practical experience. All introductory
talks will be followed by nuanced and carefully developed experiential activities prepared by
each group of presenters and delivered at the two thematically arranged round tables. Jointly,
seven interconnected presentations will address LIS pedagogy, educational policy, and
educational content from the standpoint of disability inclusion and its potential to transform LIS
education
Robotic-assisted surgery for left sided colon and rectal resections is associated with reduction in the postoperative surgical stress response and improved short-term outcomes: a cohort study
Introduction: There is growing evidence that the use of robotic-assisted surgery (RAS) in colorectal cancer resections is associated with improved short-term outcomes when compared to laparoscopic surgery (LS) or open surgery (OS), possibly through a reduced systemic inflammatory response (SIR). Serum C-reactive protein (CRP) is a sensitive SIR biomarker and its utility in the early identification of post-operative complications has been validated in a variety of surgical procedures. There remains a paucity of studies characterising post-operative SIR in RAS.
Methods: Retrospective study of a prospectively collected database of consecutive patients undergoing OS, LS and RAS for left-sided and rectal cancer in a single high-volume unit. Patient and disease characteristics, post-operative CRP levels, and clinical outcomes were reviewed, and their relationships explored within binary logistic regression and propensity scores matched models.
Results: A total of 1031 patients were included (483 OS, 376 LS, and 172 RAS). RAS and LS were associated with lower CRP levels across the first 4 post-operative days (p < 0.001) as well as reduced complications and length of stay compared to OS in unadjusted analyses. In binary logistic regression models, RAS was independently associated with lower CRP levels at Day 3 post-operatively (OR 0.35, 95% CI 0.21-0.59, p < 0.001) and a reduction in the rate of all complications (OR 0.39, 95% CI 0.26-0.56, p < 0.001) and major complications (OR 0.5, 95% CI 0.26-0.95, p = 0.036). Within a propensity scores matched model comparing LS versus RAS specifically, RAS was associated with lower post-operative CRP levels in the first two post-operative days, a lower proportion of patients with a CRP ≥ 150 mg/L at Day 3 (20.9% versus 30.5%, p = 0.036) and a lower rate of all complications (34.7% versus 46.7%, p = 0.033).
Conclusions: The present observational study shows that an RAS approach was associated with lower postoperative SIR, and a better postoperative complications profile
Microbiome preterm birth DREAM challenge: Crowdsourcing machine learning approaches to advance preterm birth research
Every year, 11% of infants are born preterm with significant health consequences, with the vaginal microbiome a risk factor for preterm birth. We crowdsource models to predict (1) preterm birth (PTB; \u3c37 \u3eweeks) or (2) early preterm birth (ePTB; \u3c32 \u3eweeks) from 9 vaginal microbiome studies representing 3,578 samples from 1,268 pregnant individuals, aggregated from public raw data via phylogenetic harmonization. The predictive models are validated on two independent unpublished datasets representing 331 samples from 148 pregnant individuals. The top-performing models (among 148 and 121 submissions from 318 teams) achieve area under the receiver operator characteristic (AUROC) curve scores of 0.69 and 0.87 predicting PTB and ePTB, respectively. Alpha diversity, VALENCIA community state types, and composition are important features in the top-performing models, most of which are tree-based methods. This work is a model for translation of microbiome data into clinically relevant predictive models and to better understand preterm birth
Characterization of Torin2, an ATP-Competitive Inhibitor of mTOR, ATM, and ATR
mTOR is a highly conserved serine/threonine protein kinase that serves as a central regulator of cell growth, survival, and autophagy. Deregulation of the PI3K/Akt/mTOR signaling pathway occurs commonly in cancer and numerous inhibitors targeting the ATP-binding site of these kinases are currently undergoing clinical evaluation. Here, we report the characterization of Torin2, a second-generation ATP-competitive inhibitor that is potent and selective for mTOR with a superior pharmacokinetic profile to previous inhibitors. Torin2 inhibited mTORC1-dependent T389 phosphorylation on S6K (RPS6KB1) with an EC[subscript 50] of 250 pmol/L with approximately 800-fold selectivity for cellular mTOR versus phosphoinositide 3-kinase (PI3K). Torin2 also exhibited potent biochemical and cellular activity against phosphatidylinositol-3 kinase–like kinase (PIKK) family kinases including ATM (EC[subscript 50], 28 nmol/L), ATR (EC[subscript 50], 35 nmol/L), and DNA-PK (EC[subscript 50], 118 nmol/L; PRKDC), the inhibition of which sensitized cells to Irradiation. Similar to the earlier generation compound Torin1 and in contrast to other reported mTOR inhibitors, Torin2 inhibited mTOR kinase and mTORC1 signaling activities in a sustained manner suggestive of a slow dissociation from the kinase. Cancer cell treatment with Torin2 for 24 hours resulted in a prolonged block in negative feedback and consequent T308 phosphorylation on Akt. These effects were associated with strong growth inhibition in vitro. Single-agent treatment with Torin2 in vivo did not yield significant efficacy against KRAS-driven lung tumors, but the combination of Torin2 with mitogen-activated protein/extracellular signal–regulated kinase (MEK) inhibitor AZD6244 yielded a significant growth inhibition. Taken together, our findings establish Torin2 as a strong candidate for clinical evaluation in a broad number of oncologic settings where mTOR signaling has a pathogenic role
New Frontiers-class Uranus Orbiter: Exploring the feasibility of achieving multidisciplinary science with a mid-scale mission
n/
Drivers of genetic diversity in secondary metabolic gene clusters within a fungal species
Drivers of genetic diversity in secondary metabolic gene clusters within a fungal speciesFilamentous fungi produce a diverse array of secondary metabolites (SMs) critical for defense, virulence, and communication. The metabolic pathways that produce SMs are found in contiguous gene clusters in fungal genomes, an atypical arrangement for metabolic pathways in other eukaryotes. Comparative studies of filamentous fungal species have shown that SM gene clusters are often either highly divergent or uniquely present in one or a handful of species, hampering efforts to determine the genetic basis and evolutionary drivers of SM gene cluster divergence. Here, we examined SM variation in 66 cosmopolitan strains of a single species, the opportunistic human pathogen Aspergillus fumigatus. Investigation of genome-wide within-species variation revealed 5 general types of variation in SM gene clusters: nonfunctional gene polymorphisms; gene gain and loss polymorphisms; whole cluster gain and loss polymorphisms; allelic polymorphisms, in which different alleles corresponded to distinct, nonhomologous clusters; and location polymorphisms, in which a cluster was found to differ in its genomic location across strains. These polymorphisms affect the function of representative A. fumigatus SM gene clusters, such as those involved in the production of gliotoxin, fumigaclavine, and helvolic acid as well as the function of clusters with undefined products. In addition to enabling the identification of polymorphisms, the detection of which requires extensive genome-wide synteny conservation (e.g., mobile gene clusters and nonhomologous cluster alleles), our approach also implicated multiple underlying genetic drivers, including point mutations, recombination, and genomic deletion and insertion events as well as horizontal gene transfer from distant fungi. Finally, most of the variants that we uncover within A. fumigatus have been previously hypothesized to contribute to SM gene cluster diversity across entire fungal classes and phyla. We suggest that the drivers of genetic diversity operating within a fungal species shown here are sufficient to explain SM cluster macroevolutionary patterns.National Science Foundation (grant
number DEB-1442113). Received by AR. U.S.
National Library of Medicine training grant (grant
number 2T15LM007450). Received by ALL.
Conselho Nacional de Desenvolvimento Cientı´fico e
573 Tecnológico. Northern Portugal Regional
Operational Programme (grant number NORTE-01-
0145-FEDER-000013). Received by FR. Fundação
de Amparo à Pesquisa do 572 Estado de São
Paulo. Received by GHG. National Institutes of
Health (grant number R01 AI065728-01). Received
by NPK. National Science Foundation (grant
number IOS-1401682). Received by JHW. The
funders had no role in study design, data collection
and analysis, decision to publish, or preparation of
the manuscript.info:eu-repo/semantics/publishedVersio
- …