Publications by authors named "Tom Lee"

56 Publications

iPSC-derived NK cells maintain high cytotoxicity and enhance in vivo tumor control in concert with T cells and anti-PD-1 therapy.

Sci Transl Med 2020 11;12(568)

Department of Medicine, University of Minnesota, Minneapolis, MN 55455, USA.

The development of immunotherapeutic monoclonal antibodies targeting checkpoint inhibitory receptors, such as programmed cell death 1 (PD-1), or their ligands, such as PD-L1, has transformed the oncology landscape. However, durable tumor regression is limited to a minority of patients. Therefore, combining immunotherapies with those targeting checkpoint inhibitory receptors is a promising strategy to bolster antitumor responses and improve response rates. Natural killer (NK) cells have the potential to augment checkpoint inhibition therapies, such as PD-L1/PD-1 blockade, because NK cells mediate both direct tumor lysis and T cell activation and recruitment. However, sourcing donor-derived NK cells for adoptive cell therapy has been limited by both cell number and quality. Thus, we developed a robust and efficient manufacturing system for the differentiation and expansion of high-quality NK cells derived from induced pluripotent stem cells (iPSCs). iPSC-derived NK (iNK) cells produced inflammatory cytokines and exerted strong cytotoxicity against an array of hematologic and solid tumors. Furthermore, we showed that iNK cells recruit T cells and cooperate with T cells and anti-PD-1 antibody, further enhancing inflammatory cytokine production and tumor lysis. Because the iNK cell derivation process uses a renewable starting material and enables the manufacturing of large numbers of doses from a single manufacture, iNK cells represent an "off-the-shelf" source of cells for immunotherapy with the capacity to target tumors and engage the adaptive arm of the immune system to make a "cold" tumor "hot" by promoting the influx of activated T cells to augment checkpoint inhibitor therapies.
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http://dx.doi.org/10.1126/scitranslmed.aaz5618DOI Listing
November 2020

The National Endoscopy Database (NED) Automated Performance Reports to Improve Quality Outcomes Trial (APRIQOT) randomized controlled trial design.

Endosc Int Open 2020 Nov 21;8(11):E1545-E1552. Epub 2020 Oct 21.

North Tees and Hartlepool NHL Foundation Trust - Gastroenterology, Stockton on Tees, United Kingdom of Great Britain and Northern Ireland.

Colonoscopists with low polyp detection have higher post colonoscopy colorectal cancer incidence and mortality rates. The United Kingdom's National Endoscopy Database (NED) automatically captures patient level data in real time and provides endoscopy key performance indicators (KPI) at a national, endoscopy center, and individual level. Using an electronic behavior change intervention, the primary objective of this study is to assess if automated feedback of endoscopist and endoscopy center-level optimal procedure-adjusted detection KPI (opadKPI) improves polyp detection performance. This multicenter, prospective, cluster-randomized controlled trial is randomizing NHS endoscopy centres to either intervention or control. The intervention is targeted at independent colonoscopists and each center's endoscopy lead. The intervention reports are evidence-based from endoscopist qualitative interviews and informed by psychological theories of behavior. NED automatically creates monthly reports providing an opadKPI, using mean number of polyps, and an action plan. The primary outcome is opadKPI comparing endoscopists in intervention and control centers at 9 months. Secondary outcomes include other KPI and proximal detection measures at 9 and 12 months. A nested histological validation study will correlate opadKPI to adenoma detection rate at the center level. A cost-effectiveness and budget impact analysis will be undertaken. If the intervention is efficacious and cost-effective, we will showcase the potential of this learning health system, which can be implemented at local and national levels to improve colonoscopy quality, and demonstrate that an automated system that collects, analyses, and disseminates real-time clinical data can deliver evidence- and theory-informed feedback.
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http://dx.doi.org/10.1055/a-1261-3151DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7584467PMC
November 2020

Meta-Analysis of the Alzheimer's Disease Human Brain Transcriptome and Functional Dissection in Mouse Models.

Cell Rep 2020 07;32(2):107908

Sage Bionetworks, Seattle, WA 98121, USA. Electronic address:

We present a consensus atlas of the human brain transcriptome in Alzheimer's disease (AD), based on meta-analysis of differential gene expression in 2,114 postmortem samples. We discover 30 brain coexpression modules from seven regions as the major source of AD transcriptional perturbations. We next examine overlap with 251 brain differentially expressed gene sets from mouse models of AD and other neurodegenerative disorders. Human-mouse overlaps highlight responses to amyloid versus tau pathology and reveal age- and sex-dependent expression signatures for disease progression. Human coexpression modules enriched for neuronal and/or microglial genes broadly overlap with mouse models of AD, Huntington's disease, amyotrophic lateral sclerosis, and aging. Other human coexpression modules, including those implicated in proteostasis, are not activated in AD models but rather following other, unexpected genetic manipulations. Our results comprise a cross-species resource, highlighting transcriptional networks altered by human brain pathophysiology and identifying correspondences with mouse models for AD preclinical studies.
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http://dx.doi.org/10.1016/j.celrep.2020.107908DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7428328PMC
July 2020

Evaluation of toxicity of aerosols from flavored e-liquids in Sprague-Dawley rats in a 90-day OECD inhalation study, complemented by transcriptomics analysis.

Arch Toxicol 2020 06 5;94(6):2179-2206. Epub 2020 May 5.

PMI S&I, Philip Morris Products S.A., Quai Jeanrenaud 5, CH-2000, Neuchâtel, Switzerland.

The use of flavoring substances is an important element in the development of reduced-risk products for adult smokers to increase product acceptance and encourage switching from cigarettes. In a first step towards characterizing the sub-chronic inhalation toxicity of neat flavoring substances, a study was conducted using a mixture of the substances in a base solution of e-liquid, where the standard toxicological endpoints of the nebulized aerosols were supplemented with transcriptomics analysis. The flavor mixture was produced by grouping 178 flavors into 26 distinct chemical groups based on structural similarities and potential metabolic and biological effects. Flavoring substances predicted to show the highest toxicological effect from each group were selected as the flavor group representatives (FGR). Following Organization for Economic Cooperation and Development Testing Guideline 413, rats were exposed to three concentrations of the FGR mixture in an e-liquid composed of nicotine (23 µg/L), propylene glycol (1520 µg/L), and vegetable glycerin (1890 µg/L), while non-flavored and no-nicotine mixtures were included as references to identify potential additive or synergistic effects between nicotine and the flavoring substances. The results indicated that the inhalation of an e-liquid containing the mixture of FGRs caused very minimal local and systemic toxic effects. In particular, there were no remarkable clinical (in-life) observations in flavored e-liquid-exposed rats. The biological effects related to exposure to the mixture of neat FGRs were limited and mainly nicotine-mediated, including changes in hematological and blood chemistry parameters and organ weight. These results indicate no significant additive biological changes following inhalation exposure to the nebulized FGR mixture above the nicotine effects measured in this sub-chronic inhalation study. In a subsequent study, e-liquids with FGR mixtures will be aerosolized by thermal treatment and assessed for toxicity.
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http://dx.doi.org/10.1007/s00204-020-02759-6DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7303093PMC
June 2020

Characterization of Antineovascularization Activity and Ocular Pharmacokinetics of Phosphoinositide 3-Kinase/Mammalian Target of Rapamycin Inhibitor GNE-947.

Drug Metab Dispos 2020 05 4;48(5):408-419. Epub 2020 Mar 4.

Genentech, Inc., South San Francisco, California (X.Liu., X.Lia., J.L., S.U., J.Chen, J.Cheng, T.L., J.L., J.N., S.S.-L., C.Q., E.S., M.W., C.E.C.A.H., T.P.H.) and QPS, Delaware Technology Park, Newark, Delaware (E.S.)

The objectives of the present study were to characterize GNE-947 for its phosphoinositide 3-kinase (PI3K) and mammalian target of rapamycin (mTOR) inhibitory activities, in vitro anti-cell migration activity in human umbilical vein endothelial cells (HUVECs), in vivo antineovascularization activity in laser-induced rat choroidal neovascular (CNV) eyes, pharmacokinetics in rabbit plasma and eyes, and ocular distribution using matrix-assisted laser desorption/ionization imaging mass spectrometry (MALDI-IMS) and autoradioluminography. Its PI3K and mTOR were 0.0005 and 0.045 µM, respectively, and its HUVEC IC was 0.093 µM. GNE-947 prevented neovascularization in the rat CNV model at 50 or 100 µg per eye with repeat dosing. After a single intravenous injection at 2.5 and 500 μg/kg in rabbits, its plasma terminal half-lives () were 9.11 and 9.59 hours, respectively. After a single intravitreal injection of a solution at 2.5 μg per eye in rabbits, its apparent values were 14.4, 16.3, and 23.2 hours in the plasma, vitreous humor, and aqueous humor, respectively. After a single intravitreal injection of a suspension at 33.5, 100, 200 μg per eye in rabbits, the were 29, 74, and 219 days in the plasma and 46, 143, and 191 days in the eyes, respectively. MALDI-IMS and autoradioluminography images show that GNE-947 did not homogenously distribute in the vitreous humor and aggregated at the injection sites after injection of the suspension, which was responsible for the long of the suspension because of the slow dissolution process. This hypothesis was supported by pharmacokinetic modeling analyses. In conclusion, the PI3K/mTOR inhibitor GNE-947 prevented neovascularization in a rat CNV model, with up to approximately 6 months after a single intravitreal injection of the suspension in rabbit eyes. SIGNIFICANCE STATEMENT: GNE-947 is a potent phosphoinositide 3-kinase/mammalian target of rapamycin inhibitor and exhibits anti-choroidal neovascular activity in rat eyes. The duration of GNE-947 in the rabbit eyes after intravitreal injection in a solution is short, with a half-life () of less than a day. However, the duration after intravitreal dose of a suspension is long, with up to 6 months due to low solubility and slow dissolution. These results indicate that intravitreal injection of a suspension for low-solubility drugs can be used to achieve long-term drug exposure.
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http://dx.doi.org/10.1124/dmd.119.089763DOI Listing
May 2020

A 6-month systems toxicology inhalation study in ApoE mice demonstrates reduced cardiovascular effects of E-vapor aerosols compared with cigarette smoke.

Am J Physiol Heart Circ Physiol 2020 03 24;318(3):H604-H631. Epub 2020 Jan 24.

Philip Morris International Research and Development, Philip Morris Products, Neuchâtel, Switzerland.

Smoking cigarettes is harmful to the cardiovascular system. Considerable attention has been paid to the reduced harm potential of alternative nicotine-containing inhalable products such as e-cigarettes. We investigated the effects of E-vapor aerosols or cigarette smoke (CS) on atherosclerosis progression, cardiovascular function, and molecular changes in the heart and aorta of female apolipoprotein E-deficient (ApoE) mice. The mice were exposed to aerosols from three different E-vapor formulations: ) carrier (propylene glycol and vegetable glycerol), ) base (carrier and nicotine), or ) test (base and flavor) or to CS from 3R4F reference cigarettes for up to 6 mo. Concentrations of CS and base or test aerosols were matched at 35 µg nicotine/L. Exposure to CS, compared with sham-exposed fresh air controls, accelerated atherosclerotic plaque formation, whereas no such effect was seen for any of the three E-vapor aerosols. Molecular changes indicated disease mechanisms related to oxidative stress and inflammation in general, plus changes in calcium regulation, and altered cytoskeletal organization and microtubule dynamics in the left ventricle. While ejection fraction, fractional shortening, cardiac output, and isovolumic contraction time remained unchanged following E-vapor aerosols exposure, the nicotine-containing base and test aerosols caused an increase in isovolumic relaxation time similar to CS. A nicotine-related increase in pulse wave velocity and arterial stiffness was also observed, but it was significantly lower for base and test aerosols than for CS. These results demonstrate that in comparison with CS, E-vapor aerosols induce substantially lower biological responses associated with smoking-related cardiovascular diseases. Analysis of key urinary oxidative stress markers and proinflammatory cytokines showed an absence of oxidative stress and inflammation in the animals exposed to E-vapor aerosols. Conversely, animals exposed to conventional cigarette smoke had high urinary levels of these markers. When compared with conventional cigarette smoke, E-vapor aerosols induced smaller atherosclerotic plaque surface area and volume. Systolic and diastolic cardiac function, as well as endothelial function, were further significantly less affected by electronic cigarette aerosols than conventional cigarette smoke. Molecular analysis demonstrated that E-vapor aerosols induce significantly smaller transcriptomic dysregulation in the heart and aorta compared with conventional cigarette smoke.
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http://dx.doi.org/10.1152/ajpheart.00613.2019DOI Listing
March 2020

Pluripotent stem cell-derived NK cells with high-affinity noncleavable CD16a mediate improved antitumor activity.

Blood 2020 02;135(6):399-410

Department of Medicine, University of California, San Diego, La Jolla, CA.

Antibody-dependent cellular cytotoxicity (ADCC) is a key effector mechanism of natural killer (NK) cells that is mediated by therapeutic monoclonal antibodies (mAbs). This process is facilitated by the Fc receptor CD16a on human NK cells. CD16a appears to be the only activating receptor on NK cells that is cleaved by the metalloprotease a disintegrin and metalloproteinase-17 upon stimulation. We previously demonstrated that a point mutation of CD16a prevents this activation-induced surface cleavage. This noncleavable CD16a variant is now further modified to include the high-affinity noncleavable variant of CD16a (hnCD16) and was engineered into human induced pluripotent stem cells (iPSCs) to create a renewable source for human induced pluripotent stem cell-derived NK (hnCD16-iNK) cells. Compared with unmodified iNK cells and peripheral blood-derived NK (PB-NK) cells, hnCD16-iNK cells proved to be highly resistant to activation-induced cleavage of CD16a. We found that hnCD16-iNK cells were functionally mature and exhibited enhanced ADCC against multiple tumor targets. In vivo xenograft studies using a human B-cell lymphoma demonstrated that treatment with hnCD16-iNK cells and anti-CD20 mAb led to significantly improved regression of B-cell lymphoma compared with treatment utilizing anti-CD20 mAb with PB-NK cells or unmodified iNK cells. hnCD16-iNK cells, combined with anti-HER2 mAb, also mediated improved survival in an ovarian cancer xenograft model. Together, these findings show that hnCD16-iNK cells combined with mAbs are highly effective against hematologic malignancies and solid tumors that are typically resistant to NK cell-mediated killing, demonstrating the feasibility of producing a standardized off-the-shelf engineered NK cell therapy with improved ADCC properties to treat malignancies that are otherwise refractory.
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http://dx.doi.org/10.1182/blood.2019000621DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7005364PMC
February 2020

Genetic architecture of subcortical brain structures in 38,851 individuals.

Authors:
Claudia L Satizabal Hieab H H Adams Derrek P Hibar Charles C White Maria J Knol Jason L Stein Markus Scholz Muralidharan Sargurupremraj Neda Jahanshad Gennady V Roshchupkin Albert V Smith Joshua C Bis Xueqiu Jian Michelle Luciano Edith Hofer Alexander Teumer Sven J van der Lee Jingyun Yang Lisa R Yanek Tom V Lee Shuo Li Yanhui Hu Jia Yu Koh John D Eicher Sylvane Desrivières Alejandro Arias-Vasquez Ganesh Chauhan Lavinia Athanasiu Miguel E Rentería Sungeun Kim David Hoehn Nicola J Armstrong Qiang Chen Avram J Holmes Anouk den Braber Iwona Kloszewska Micael Andersson Thomas Espeseth Oliver Grimm Lucija Abramovic Saud Alhusaini Yuri Milaneschi Martina Papmeyer Tomas Axelsson Stefan Ehrlich Roberto Roiz-Santiañez Bernd Kraemer Asta K Håberg Hannah J Jones G Bruce Pike Dan J Stein Allison Stevens Janita Bralten Meike W Vernooij Tamara B Harris Irina Filippi A Veronica Witte Tulio Guadalupe Katharina Wittfeld Thomas H Mosley James T Becker Nhat Trung Doan Saskia P Hagenaars Yasaman Saba Gabriel Cuellar-Partida Najaf Amin Saima Hilal Kwangsik Nho Nazanin Mirza-Schreiber Konstantinos Arfanakis Diane M Becker David Ames Aaron L Goldman Phil H Lee Dorret I Boomsma Simon Lovestone Sudheer Giddaluru Stephanie Le Hellard Manuel Mattheisen Marc M Bohlken Dalia Kasperaviciute Lianne Schmaal Stephen M Lawrie Ingrid Agartz Esther Walton Diana Tordesillas-Gutierrez Gareth E Davies Jean Shin Jonathan C Ipser Louis N Vinke Martine Hoogman Tianye Jia Ralph Burkhardt Marieke Klein Fabrice Crivello Deborah Janowitz Owen Carmichael Unn K Haukvik Benjamin S Aribisala Helena Schmidt Lachlan T Strike Ching-Yu Cheng Shannon L Risacher Benno Pütz Debra A Fleischman Amelia A Assareh Venkata S Mattay Randy L Buckner Patrizia Mecocci Anders M Dale Sven Cichon Marco P Boks Mar Matarin Brenda W J H Penninx Vince D Calhoun M Mallar Chakravarty Andre F Marquand Christine Macare Shahrzad Kharabian Masouleh Jaap Oosterlaan Philippe Amouyel Katrin Hegenscheid Jerome I Rotter Andrew J Schork David C M Liewald Greig I de Zubicaray Tien Yin Wong Li Shen Philipp G Sämann Henry Brodaty Joshua L Roffman Eco J C de Geus Magda Tsolaki Susanne Erk Kristel R van Eijk Gianpiero L Cavalleri Nic J A van der Wee Andrew M McIntosh Randy L Gollub Kazima B Bulayeva Manon Bernard Jennifer S Richards Jayandra J Himali Markus Loeffler Nanda Rommelse Wolfgang Hoffmann Lars T Westlye Maria C Valdés Hernández Narelle K Hansell Theo G M van Erp Christiane Wolf John B J Kwok Bruno Vellas Andreas Heinz Loes M Olde Loohuis Norman Delanty Beng-Choon Ho Christopher R K Ching Elena Shumskaya Baljeet Singh Albert Hofman Dennis van der Meer Georg Homuth Bruce M Psaty Mark E Bastin Grant W Montgomery Tatiana M Foroud Simone Reppermund Jouke-Jan Hottenga Andrew Simmons Andreas Meyer-Lindenberg Wiepke Cahn Christopher D Whelan Marjolein M J van Donkelaar Qiong Yang Norbert Hosten Robert C Green Anbupalam Thalamuthu Sebastian Mohnke Hilleke E Hulshoff Pol Honghuang Lin Clifford R Jack Peter R Schofield Thomas W Mühleisen Pauline Maillard Steven G Potkin Wei Wen Evan Fletcher Arthur W Toga Oliver Gruber Matthew Huentelman George Davey Smith Lenore J Launer Lars Nyberg Erik G Jönsson Benedicto Crespo-Facorro Nastassja Koen Douglas N Greve André G Uitterlinden Daniel R Weinberger Vidar M Steen Iryna O Fedko Nynke A Groenewold Wiro J Niessen Roberto Toro Christophe Tzourio William T Longstreth M Kamran Ikram Jordan W Smoller Marie-Jose van Tol Jessika E Sussmann Tomas Paus Hervé Lemaître Matthias L Schroeter Bernard Mazoyer Ole A Andreassen Florian Holsboer Chantal Depondt Dick J Veltman Jessica A Turner Zdenka Pausova Gunter Schumann Daan van Rooij Srdjan Djurovic Ian J Deary Katie L McMahon Bertram Müller-Myhsok Rachel M Brouwer Hilkka Soininen Massimo Pandolfo Thomas H Wassink Joshua W Cheung Thomas Wolfers Jean-Luc Martinot Marcel P Zwiers Matthias Nauck Ingrid Melle Nicholas G Martin Ryota Kanai Eric Westman René S Kahn Sanjay M Sisodiya Tonya White Arvin Saremi Hans van Bokhoven Han G Brunner Henry Völzke Margaret J Wright Dennis van 't Ent Markus M Nöthen Roel A Ophoff Jan K Buitelaar Guillén Fernández Perminder S Sachdev Marcella Rietschel Neeltje E M van Haren Simon E Fisher Alexa S Beiser Clyde Francks Andrew J Saykin Karen A Mather Nina Romanczuk-Seiferth Catharina A Hartman Anita L DeStefano Dirk J Heslenfeld Michael W Weiner Henrik Walter Pieter J Hoekstra Paul A Nyquist Barbara Franke David A Bennett Hans J Grabe Andrew D Johnson Christopher Chen Cornelia M van Duijn Oscar L Lopez Myriam Fornage Joanna M Wardlaw Reinhold Schmidt Charles DeCarli Philip L De Jager Arno Villringer Stéphanie Debette Vilmundur Gudnason Sarah E Medland Joshua M Shulman Paul M Thompson Sudha Seshadri M Arfan Ikram

Nat Genet 2019 11 21;51(11):1624-1636. Epub 2019 Oct 21.

Department of Epidemiology, Erasmus MC, Rotterdam, the Netherlands.

Subcortical brain structures are integral to motion, consciousness, emotions and learning. We identified common genetic variation related to the volumes of the nucleus accumbens, amygdala, brainstem, caudate nucleus, globus pallidus, putamen and thalamus, using genome-wide association analyses in almost 40,000 individuals from CHARGE, ENIGMA and UK Biobank. We show that variability in subcortical volumes is heritable, and identify 48 significantly associated loci (40 novel at the time of analysis). Annotation of these loci by utilizing gene expression, methylation and neuropathological data identified 199 genes putatively implicated in neurodevelopment, synaptic signaling, axonal transport, apoptosis, inflammation/infection and susceptibility to neurological disorders. This set of genes is significantly enriched for Drosophila orthologs associated with neurodevelopmental phenotypes, suggesting evolutionarily conserved mechanisms. Our findings uncover novel biology and potential drug targets underlying brain development and disease.
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http://dx.doi.org/10.1038/s41588-019-0511-yDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7055269PMC
November 2019

A Portal to Visualize Transcriptome Profiles in Mouse Models of Neurological Disorders.

Genes (Basel) 2019 09 26;10(10). Epub 2019 Sep 26.

Department of Pediatrics, Baylor College of Medicine, Houston, TX 77030, USA.

Target nomination for drug development has been a major challenge in the path to finding a cure for several neurological disorders. Comprehensive transcriptome profiles have revealed brain gene expression changes associated with many neurological disorders, and the functional validation of these changes is a critical next step. Model organisms are a proven approach for the elucidation of disease mechanisms, including screening of gene candidates as therapeutic targets. Frequently, multiple models exist for a given disease, creating a challenge to select the optimal model for validation and functional follow-up. To help in nominating the best mouse models for studying neurological diseases, we developed a web portal to visualize mouse transcriptomic data related to neurological disorders: http://mmad.nrihub.org. Users can examine gene expression changes across mouse model studies to help select the optimal mouse model for further investigation. The portal provides access to mouse studies related to Alzheimer's diseases (AD), Parkinson's disease (PD), Huntington's disease (HD), Amyotrophic Lateral Sclerosis (ALS), Spinocerebellar ataxia (SCA), and models related to aging.
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http://dx.doi.org/10.3390/genes10100759DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6826490PMC
September 2019

cindr, the Drosophila Homolog of the CD2AP Alzheimer's Disease Risk Gene, Is Required for Synaptic Transmission and Proteostasis.

Cell Rep 2019 08;28(7):1799-1813.e5

Department of Neurology, Baylor College of Medicine, Houston, TX 77030, USA; Jan and Dan Duncan Neurologic Research Institute, Texas Children's Hospital, Houston, TX 77030, USA; Program in Developmental Biology, Baylor College of Medicine, Houston, TX 77030, USA; Department of Molecular & Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA; Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030, USA. Electronic address:

The Alzheimer's disease (AD) susceptibility gene, CD2-associated protein (CD2AP), encodes an actin binding adaptor protein, but its function in the nervous system is largely unknown. Loss of the Drosophila ortholog cindr enhances neurotoxicity of human Tau, which forms neurofibrillary tangle pathology in AD. We show that Cindr is expressed in neurons and present at synaptic terminals. cindr mutants show impairments in synapse maturation and both synaptic vesicle recycling and release. Cindr associates and genetically interacts with 14-3-3ζ, regulates the ubiquitin-proteasome system, and affects turnover of Synapsin and the plasma membrane calcium ATPase (PMCA). Loss of cindr elevates PMCA levels and reduces cytosolic calcium. Studies of Cd2ap null mice support a conserved role in synaptic proteostasis, and CD2AP protein levels are inversely related to Synapsin abundance in human postmortem brains. Our results reveal CD2AP neuronal requirements with relevance to AD susceptibility, including for proteostasis, calcium handling, and synaptic structure and function.
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http://dx.doi.org/10.1016/j.celrep.2019.07.041DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6703184PMC
August 2019

Sensitized genetic backgrounds reveal differential roles for EGF repeat xylosyltransferases in Drosophila Notch signaling.

Glycobiology 2018 11;28(11):849-859

Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA.

In multicellular organisms, glycosylation regulates various developmental signaling pathways including the Notch pathway. One of the O-linked glycans added to epidermal growth factor-like (EGF) repeats in animal proteins including the Notch receptors is the xylose-xylose-glucose-O oligosaccharide. Drosophila glucoside xylosyltransferase (Gxylt) Shams negatively regulates Notch signaling in specific contexts. Since Shams adds the first xylose residue to O-glucose, its loss-of-function phenotype could be due to the loss of the first xylose, the second xylose or both. To examine the contribution of the second xylose residues to Drosophila Notch signaling, we have performed biochemical and genetic analysis on CG11388, which is the Drosophila homolog of human xyloside xylosyltransferase 1 (XXYLT1). Experiments in S2 cells indicated that similar to human XXYLT1, CG11388 can add the second xylose to xylose-glucose-O glycans. Flies lacking both copies of CG11388 (Xxylt) are viable and fertile and do not show gross phenotypes indicative of altered Notch signaling. However, genetic interaction experiments show that in sensitized genetic backgrounds with decreased or increased Notch pathway components, loss of Xxylt promotes Delta-mediated activation of Notch. Unexpectedly, we find that in such sensitized backgrounds, even loss of one copy of the fly Gxylt shams enhances Delta-mediated Notch activation. Taken together, these data indicate that while the first xylose plays a key role in tuning the Delta-mediated Notch signaling in Drosophila, the second xylose has a fine-tuning role only revealed in sensitized genetic backgrounds.
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http://dx.doi.org/10.1093/glycob/cwy080DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6454539PMC
November 2018

Defects in the Neuroendocrine Axis Contribute to Global Development Delay in a Model of NGLY1 Deficiency.

G3 (Bethesda) 2018 07 2;8(7):2193-2204. Epub 2018 Jul 2.

Perlara PBC, 6000 Shoreline Court, Suite 204, South San Francisco, California 94080.

N-glycanase 1 (NGLY1) Deficiency is a rare monogenic multi-system disorder first described in 2014. is evolutionarily conserved in model organisms. Here we conducted a natural history study and chemical-modifier screen on the homolog, We generated a new fly model of NGLY1 Deficiency, engineered with a nonsense mutation in at codon 420 that results in a truncation of the C-terminal carbohydrate-binding PAW domain. Homozygous mutant animals exhibit global development delay, pupal lethality and small body size as adults. We developed a 96-well-plate, image-based, quantitative assay of larval size for use in a screen of the 2,650-member Microsource Spectrum compound library of FDA approved drugs, bioactive tool compounds, and natural products. We found that the cholesterol-derived ecdysteroid molting hormone 20-hydroxyecdysone (20E) partially rescued the global developmental delay in mutant homozygotes. Targeted expression of a human NGLY1 transgene to tissues involved in ecdysteroidogenesis, , prothoracic gland, also partially rescues global developmental delay in mutant homozygotes. Finally, the proteasome inhibitor bortezomib is a potent enhancer of global developmental delay in our fly model, evidence of a defective proteasome "bounce-back" response that is also observed in nematode and cellular models of NGLY1 Deficiency. Together, these results demonstrate the therapeutic relevance of a new fly model of NGLY1 Deficiency for drug discovery and gene modifier screens.
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http://dx.doi.org/10.1534/g3.118.300578DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6027897PMC
July 2018

A Single Mutation Traps a Half-Sites Reactive Enzyme in Midstream, Explaining Asymmetry in Hydride Transfer.

Biochemistry 2018 05 2;57(19):2786-2795. Epub 2018 May 2.

Department of Biochemistry and Biophysics , University of California , San Francisco , California 94143-2240 , United States.

In Escherichia coli thymidylate synthase (EcTS), rate-determining hydride transfer from the cofactor 5,10-methylene-5,6,7,8-tetrahydrofolate to the intermediate 5-methylene-2'-deoxyuridine 5'-monophosphate occurs by hydrogen tunneling, requiring precise alignment of reactants and a closed binding cavity, sealed by the C-terminal carboxyl group. Mutations that destabilize the closed conformation of the binding cavity allow small molecules such as β-mercaptoethanol (β-ME) to enter the active site and compete with hydride for addition to the 5-methylene group of the intermediate. The C-terminal deletion mutant of EcTS produced the β-ME adduct in proportions that varied dramatically with cofactor concentration, from 50% at low cofactor concentrations to 0% at saturating cofactor conditions, suggesting communication between active sites. We report the 2.4 Å X-ray structure of the C-terminal deletion mutant of E. coli TS in complex with a substrate and a cofactor analogue, CB3717. The structure is asymmetric, with reactants aligned in a manner consistent with hydride transfer in only one active site. In the second site, CB3717 has shifted to a site where the normal cofactor would be unlikely to form 5-methylene-2'-deoxyuridine 5'-monophosphate, consistent with no formation of the β-ME adduct. The structure shows how the binding of the cofactor at one site triggers hydride transfer and borrows needed stabilization from substrate binding at the second site. It indicates pathways through the dimer interface that contribute to allostery relevant to half-sites reactivity.
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http://dx.doi.org/10.1021/acs.biochem.8b00176DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6242337PMC
May 2018

A 90-day OECD TG 413 rat inhalation study with systems toxicology endpoints demonstrates reduced exposure effects of the aerosol from the carbon heated tobacco product version 1.2 (CHTP1.2) compared with cigarette smoke. I. Inhalation exposure, clinical pathology and histopathology.

Food Chem Toxicol 2018 Jun 11;116(Pt B):388-413. Epub 2018 Apr 11.

PMI R&D, Philip Morris Products S.A., Quai Jeanrenaud 5, CH-2000 Neuchatel, Switzerland. Electronic address:

Within the framework of a systems toxicology approach, the inhalation toxicity of aerosol from a novel tobacco-heating potentially modified risk tobacco product (MRTP), the carbon-heated tobacco product (CHTP) 1.2, was characterized and compared with that of mainstream smoke (CS) from the 3R4F reference cigarette in a 90-day nose-only rat inhalation study in general accordance with OECD TG 413. CHTP1.2 is a heat-not-burn product using a carbon heat source to produce an aerosol that contains nicotine and tobacco flavor. At equal or twice the nicotine concentration in the test atmospheres, inhalation of CHTP1.2 aerosol led to a significantly lower exposure to harmful constituents and induced less respiratory tract irritation, systemic, and pathological effects compared with CS. Nasal epithelial changes were less pronounced in the CHTP1.2- than in the CS-exposed groups and reverted in the nicotine concentration-matched group after a recovery period. Lung inflammation was minimal in the CHTP1.2-treated groups compared with the moderate extent seen in the 3R4F groups. Many other toxicological endpoints evaluated did not show CHTP1.2 aerosol exposure-related effects, and no effects not seen for 3R4F were observed. These observations were consistent with findings from previous studies in which rats were exposed to MRTP aerosols containing similar nicotine concentrations.
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http://dx.doi.org/10.1016/j.fct.2018.04.015DOI Listing
June 2018

CT brain artefact due to air bubbles in the oil cooling system: characteristic band-like configuration on sagittal reformatted image.

Jpn J Radiol 2018 Feb 8;36(2):90-95. Epub 2017 Nov 8.

Department of Imaging and Interventional Radiology, Prince of Wales Hospital, Hong Kong Special Administrative Region, People's Republic of China.

Purpose: To retrospectively review the imaging characteristics of CT artefacts due to air bubbles within the oil cooling system of the X-ray tube housing.

Materials And Methods: Air bubbles were introduced into the oil cooling system of the X-ray tube housing during tube replacement in one of the CT scanners in the authors' institution. All 126 CT brain studies performed in this period were retrospectively reviewed. One hundred and four studies were negative for artefacts. Artefacts were confirmed in 5 and considered probable in 17 studies, respectively. The imaging characteristics of artefacts in these 22 cases were analysed.

Results: All artefacts manifested as ill-defined hypoattenuations in the periventricular/subcortical white matter of bilateral cerebral hemispheres with/without involvement of the internal capsule and basal ganglia. The posterior fossa was also involved in two (40%) confirmed and four (24%) probable studies. A band-like configuration of hypoattenuations on sagittal images was observed in five (100%) confirmed and eight (47%) probable studies.

Conclusion: Air bubble artefacts manifested as hypoattenuations in the periventricular/subcortical white matter of the supratentorial brain. A characteristic band-like configuration was observed in the sagittal reformatted image, which is useful for differentiating it from periventricular small vessel disease.
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http://dx.doi.org/10.1007/s11604-017-0702-3DOI Listing
February 2018

Cardiotrophin 1 stimulates beneficial myogenic and vascular remodeling of the heart.

Cell Res 2017 Oct 8;27(10):1195-1215. Epub 2017 Aug 8.

Sprott Centre for Stem Cell Research, Regenerative Medicine Program, Ottawa Hospital Research Institute, Ottawa Hospital, Ottawa, Ontario K1H 8L6, Canada.

The post-natal heart adapts to stress and overload through hypertrophic growth, a process that may be pathologic or beneficial (physiologic hypertrophy). Physiologic hypertrophy improves cardiac performance in both healthy and diseased individuals, yet the mechanisms that propagate this favorable adaptation remain poorly defined. We identify the cytokine cardiotrophin 1 (CT1) as a factor capable of recapitulating the key features of physiologic growth of the heart including transient and reversible hypertrophy of the myocardium, and stimulation of cardiomyocyte-derived angiogenic signals leading to increased vascularity. The capacity of CT1 to induce physiologic hypertrophy originates from a CK2-mediated restraining of caspase activation, preventing the transition to unrestrained pathologic growth. Exogenous CT1 protein delivery attenuated pathology and restored contractile function in a severe model of right heart failure, suggesting a novel treatment option for this intractable cardiac disease.
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http://dx.doi.org/10.1038/cr.2017.87DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5630684PMC
October 2017

Imprinted NanoVelcro Microchips for Isolation and Characterization of Circulating Fetal Trophoblasts: Toward Noninvasive Prenatal Diagnostics.

ACS Nano 2017 08 19;11(8):8167-8177. Epub 2017 Jul 19.

California NanoSystems Institute, Crump Institute for Molecular Imaging, Department of Molecular and Medical Pharmacology, University of California, Los Angeles , Los Angeles, California 90095-1770, United States.

Circulating fetal nucleated cells (CFNCs) in maternal blood offer an ideal source of fetal genomic DNA for noninvasive prenatal diagnostics (NIPD). We developed a class of nanoVelcro microchips to effectively enrich a subcategory of CFNCs, i.e., circulating trophoblasts (cTBs) from maternal blood, which can then be isolated with single-cell resolution by a laser capture microdissection (LCM) technique for downstream genetic testing. We first established a nanoimprinting fabrication process to prepare the LCM-compatible nanoVelcro substrates. Using an optimized cTB-capture condition and an immunocytochemistry protocol, we were able to identify and isolate single cTBs (Hoechst+/CK7+/HLA-G+/CD45-, 20 μm > sizes > 12 μm) on the imprinted nanoVelcro microchips. Three cTBs were polled to ensure reproducible whole genome amplification on the cTB-derived DNA, paving the way for cTB-based array comparative genomic hybridization (aCGH) and short tandem repeats analysis. Using maternal blood samples collected from expectant mothers carrying a single fetus, the cTB-derived aCGH data were able to detect fetal genders and chromosomal aberrations, which had been confirmed by standard clinical practice. Our results support the use of nanoVelcro microchips for cTB-based noninvasive prenatal genetic testing, which holds potential for further development toward future NIPD solution.
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http://dx.doi.org/10.1021/acsnano.7b03073DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5614709PMC
August 2017

Xylosylation of the Notch receptor preserves the balance between its activation by trans-Delta and inhibition by cis-ligands in Drosophila.

PLoS Genet 2017 04 10;13(4):e1006723. Epub 2017 Apr 10.

Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America.

The Drosophila glucoside xylosyltransferase Shams xylosylates Notch and inhibits Notch signaling in specific contexts including wing vein development. However, the molecular mechanisms underlying context-specificity of the shams phenotype is not known. Considering the role of Delta-Notch signaling in wing vein formation, we hypothesized that Shams might affect Delta-mediated Notch signaling in Drosophila. Using genetic interaction studies, we find that altering the gene dosage of Delta affects the wing vein and head bristle phenotypes caused by loss of Shams or by mutations in the Notch xylosylation sites. Clonal analysis suggests that loss of shams promotes Delta-mediated Notch activation. Further, Notch trans-activation by ectopically overexpressed Delta shows a dramatic increase upon loss of shams. In agreement with the above in vivo observations, cell aggregation and ligand-receptor binding assays show that shams knock-down in Notch-expressing cells enhances the binding between Notch and trans-Delta without affecting the binding between Notch and trans-Serrate and cell surface levels of Notch. Loss of Shams does not impair the cis-inhibition of Notch by ectopic overexpression of ligands in vivo or the interaction of Notch and cis-ligands in S2 cells. Nevertheless, removing one copy of endogenous ligands mimics the effects of loss shams on Notch trans-activation by ectopic Delta. This favors the notion that trans-activation of Notch by Delta overcomes the cis-inhibition of Notch by endogenous ligands upon loss of shams. Taken together, our data suggest that xylosylation selectively impedes the binding of Notch with trans-Delta without affecting its binding with cis-ligands and thereby assists in determining the balance of Notch receptor's response to cis-ligands vs. trans-Delta during Drosophila development.
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http://dx.doi.org/10.1371/journal.pgen.1006723DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5402982PMC
April 2017

A POGLUT1 mutation causes a muscular dystrophy with reduced Notch signaling and satellite cell loss.

EMBO Mol Med 2016 11 2;8(11):1289-1309. Epub 2016 Nov 2.

Neuromuscular Disorders Unit, Department of Neurology, Instituto de Biomedicina de Sevilla, Hospital U. Virgen del Rocío/CSIC/Universidad de Sevilla, Sevilla, Spain

Skeletal muscle regeneration by muscle satellite cells is a physiological mechanism activated upon muscle damage and regulated by Notch signaling. In a family with autosomal recessive limb-girdle muscular dystrophy, we identified a missense mutation in POGLUT1 (protein O-glucosyltransferase 1), an enzyme involved in Notch posttranslational modification and function. In vitro and in vivo experiments demonstrated that the mutation reduces O-glucosyltransferase activity on Notch and impairs muscle development. Muscles from patients revealed decreased Notch signaling, dramatic reduction in satellite cell pool and a muscle-specific α-dystroglycan hypoglycosylation not present in patients' fibroblasts. Primary myoblasts from patients showed slow proliferation, facilitated differentiation, and a decreased pool of quiescent PAX7 cells. A robust rescue of the myogenesis was demonstrated by increasing Notch signaling. None of these alterations were found in muscles from secondary dystroglycanopathy patients. These data suggest that a key pathomechanism for this novel form of muscular dystrophy is Notch-dependent loss of satellite cells.
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http://dx.doi.org/10.15252/emmm.201505815DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5090660PMC
November 2016

Linear topology in amorphous metal oxide electrochromic networks obtained via low-temperature solution processing.

Nat Mater 2016 12 22;15(12):1267-1273. Epub 2016 Aug 22.

The Molecular Foundry, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, California 94720, USA.

Amorphous transition metal oxides are recognized as leading candidates for electrochromic window coatings that can dynamically modulate solar irradiation and improve building energy efficiency. However, their thin films are normally prepared by energy-intensive sputtering techniques or high-temperature solution methods, which increase manufacturing cost and complexity. Here, we report on a room-temperature solution process to fabricate electrochromic films of niobium oxide glass (NbO) and 'nanocrystal-in-glass' composites (that is, tin-doped indium oxide (ITO) nanocrystals embedded in NbO glass) via acid-catalysed condensation of polyniobate clusters. A combination of X-ray scattering and spectroscopic characterization with complementary simulations reveals that this strategy leads to a unique one-dimensional chain-like NbO structure, which significantly enhances the electrochromic performance, compared to a typical three-dimensional NbO network obtained from conventional high-temperature thermal processing. In addition, we show how self-assembled ITO-in-NbO composite films can be successfully integrated into high-performance flexible electrochromic devices.
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http://dx.doi.org/10.1038/nmat4734DOI Listing
December 2016

Interview with Tom X. Lee, MD.

Healthc (Amst) 2015 Dec 22;3(4):291-2. Epub 2014 Nov 22.

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http://dx.doi.org/10.1016/j.hjdsi.2014.11.003DOI Listing
December 2015

A comparison of isolated circulating tumor cells and tissue biopsies using whole-genome sequencing in prostate cancer.

Oncotarget 2015 Dec;6(42):44781-93

Urologic Oncology Research Program, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA.

Previous studies have demonstrated focal but limited molecular similarities between circulating tumor cells (CTCs) and biopsies using isolated genetic assays. We hypothesized that molecular similarity between CTCs and tissue exists at the single cell level when characterized by whole genome sequencing (WGS). By combining the NanoVelcro CTC Chip with laser capture microdissection (LCM), we developed a platform for single-CTC WGS. We performed this procedure on CTCs and tissue samples from a patient with advanced prostate cancer who had serial biopsies over the course of his clinical history. We achieved 30X depth and ≥ 95% coverage. Twenty-nine percent of the somatic single nucleotide variations (SSNVs) identified were founder mutations that were also identified in CTCs. In addition, 86% of the clonal mutations identified in CTCs could be traced back to either the primary or metastatic tumors. In this patient, we identified structural variations (SVs) including an intrachromosomal rearrangement in chr3 and an interchromosomal rearrangement between chr13 and chr15. These rearrangements were shared between tumor tissues and CTCs. At the same time, highly heterogeneous short structural variants were discovered in PTEN, RB1, and BRCA2 in all tumor and CTC samples. Using high-quality WGS on single-CTCs, we identified the shared genomic alterations between CTCs and tumor tissues. This approach yielded insight into the heterogeneity of the mutational landscape of SSNVs and SVs. It may be possible to use this approach to study heterogeneity and characterize the biological evolution of a cancer during the course of its natural history.
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http://dx.doi.org/10.18632/oncotarget.6330DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4792591PMC
December 2015

Optimizing the back office.

Authors:
Tom S Lee

Healthc Financ Manage 2015 Sep;69(9):88-92, 94

The shift to value-based service calls for new attention to be paid to an area often ignored in such a system: the back office. To reduce administrative costs and maximize compensation, healthcare providers should: Stay current with rules and timelines. Monitor provider eligibility and performance. Prepare for performance data submission.
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September 2015

The Value of Pre- and Intraoperative Adjuncts on the Extent of Resection of Hemispheric Low-Grade Gliomas: A Retrospective Analysis.

J Neurol Surg A Cent Eur Neurosurg 2016 Mar 27;77(2):79-87. Epub 2015 Jul 27.

Department of Neurosurgery, Brigham and Women's Hospital, Boston, Massachusetts, United States.

Background: To achieve maximal resection with minimal risk of postoperative neurologic morbidity, different neurosurgical adjuncts are being used during low-grade glioma (LGG) surgery.

Objectives: To investigate the effect of pre- and intraoperative adjuncts on the extent of resection (EOR) of hemispheric LGGs.

Methods: Medical records were reviewed to identify patients of any sex, ≥ 18 years of age, who underwent LGG surgery at X Hospital between January 2005 and July 2013. Patients were divided into eight subgroups based on the use of various combinations of a neuronavigation system alone (NN), functional MRI-diffusion tensor imaging (fMRI-DTI) guided neuronavigation (FD), intraoperative MRI (MR), and direct electrical stimulation (DES). Initial and residual tumors were measured, and mean EOR was compared between groups.

Results: Of all 128 patients, gross total resection was achieved in 23.4%. Overall mean EOR was 81.3% ± 20.5%. Using DES in combination with fMRI-DTI (mean EOR: 86.7% ± 12.4%) on eloquent tumors improved mean EOR significantly after adjustment for potential confounders when compared with NN alone (mean EOR: 76.4% ± 25.5%; p = 0.001).

Conclusions: Using DES in combination with fMRI and DTI significantly improves EOR when LGGs are located in eloquent areas compared with craniotomies in which only NN was used.
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http://dx.doi.org/10.1055/s-0035-1551830DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4836365PMC
March 2016

Programming thermoresponsiveness of NanoVelcro substrates enables effective purification of circulating tumor cells in lung cancer patients.

ACS Nano 2015 Jan 17;9(1):62-70. Epub 2014 Dec 17.

Department of Pathology, The First Affiliated Hospital of Sun Yat-Sen University , Guangzhou, Guangdong 510080, P.R. China.

Unlike tumor biopsies that can be constrained by problems such as sampling bias, circulating tumor cells (CTCs) are regarded as the "liquid biopsy" of the tumor, providing convenient access to all disease sites, including primary tumor and fatal metastases. Although enumerating CTCs is of prognostic significance in solid tumors, it is conceivable that performing molecular and functional analyses on CTCs will reveal much significant insight into tumor biology to guide proper therapeutic intervention. We developed the Thermoresponsive NanoVelcro CTC purification system that can be digitally programmed to achieve an optimal performance for purifying CTCs from non-small cell lung cancer (NSCLC) patients. The performance of this unique CTC purification system was optimized by systematically modulating surface chemistry, flow rates, and heating/cooling cycles. By applying a physiologically endurable stimulation (i.e., temperature between 4 and 37 °C), the mild operational parameters allow minimum disruption to CTCs' viability and molecular integrity. Subsequently, we were able to successfully demonstrate culture expansion and mutational analysis of the CTCs purified by this CTC purification system. Most excitingly, we adopted the combined use of the Thermoresponsive NanoVelcro system with downstream mutational analysis to monitor the disease evolution of an index NSCLC patient, highlighting its translational value in managing NSCLC.
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http://dx.doi.org/10.1021/nn5056282DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4310634PMC
January 2015

The protein O-glucosyltransferase Rumi modifies eyes shut to promote rhabdomere separation in Drosophila.

PLoS Genet 2014 Nov 20;10(11):e1004795. Epub 2014 Nov 20.

Program in Genes & Development, The University of Texas Graduate School of Biomedical Sciences, Houston, Texas, United States of America; Department of Molecular & Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America; Program in Developmental Biology, Baylor College of Medicine, Houston, Texas, United States of America.

The protein O-glucosyltransferase Rumi/POGLUT1 regulates Drosophila Notch signaling by adding O-glucose residues to the Notch extracellular domain. Rumi has other predicted targets including Crumbs (Crb) and Eyes shut (Eys), both of which are involved in photoreceptor development. However, whether Rumi is required for the function of Crb and Eys remains unknown. Here we report that in the absence of Rumi or its enzymatic activity, several rhabdomeres in each ommatidium fail to separate from one another in a Notch-independent manner. Mass spectral analysis indicates the presence of O-glucose on Crb and Eys. However, mutating all O-glucosylation sites in a crb knock-in allele does not cause rhabdomere attachment, ruling out Crb as a biologically-relevant Rumi target in this process. In contrast, eys and rumi exhibit a dosage-sensitive genetic interaction. In addition, although in wild-type ommatidia most of the Eys protein is found in the inter-rhabdomeral space (IRS), in rumi mutants a significant fraction of Eys remains in the photoreceptor cells. The intracellular accumulation of Eys and the IRS defect worsen in rumi mutants raised at a higher temperature, and are accompanied by a ∼50% decrease in the total level of Eys. Moreover, removing one copy of an endoplasmic reticulum chaperone enhances the rhabdomere attachment in rumi mutant animals. Altogether, our data suggest that O-glucosylation of Eys by Rumi ensures rhabdomere separation by promoting proper Eys folding and stability in a critical time window during the mid-pupal stage. Human EYS, which is mutated in patients with autosomal recessive retinitis pigmentosa, also harbors multiple Rumi target sites. Therefore, the role of O-glucose in regulating Eys may be conserved.
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http://dx.doi.org/10.1371/journal.pgen.1004795DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4238978PMC
November 2014

Fringe proteins modulate Notch-ligand cis and trans interactions to specify signaling states.

Elife 2014 Sep 25;3:e02950. Epub 2014 Sep 25.

Howard Hughes Medical Institute, California Institute of Technology, Pasadena, United States.

The Notch signaling pathway consists of multiple types of receptors and ligands, whose interactions can be tuned by Fringe glycosyltransferases. A major challenge is to determine how these components control the specificity and directionality of Notch signaling in developmental contexts. Here, we analyzed same-cell (cis) Notch-ligand interactions for Notch1, Dll1, and Jag1, and their dependence on Fringe protein expression in mammalian cells. We found that Dll1 and Jag1 can cis-inhibit Notch1, and Fringe proteins modulate these interactions in a way that parallels their effects on trans interactions. Fringe similarly modulated Notch-ligand cis interactions during Drosophila development. Based on these and previously identified interactions, we show how the design of the Notch signaling pathway leads to a restricted repertoire of signaling states that promote heterotypic signaling between distinct cell types, providing insight into the design principles of the Notch signaling system, and the specific developmental process of Drosophila dorsal-ventral boundary formation.
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http://dx.doi.org/10.7554/eLife.02950DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4174579PMC
September 2014

Determining who should oversee meaningful use.

Authors:
Tom S Lee

Healthc Financ Manage 2014 Aug;68(8):40-2

Although initial efforts to achieve meaningful use of electronic health records often were launched by key technical staff, these individuals may not be the best-suited to manage a meaningfuluse program over the long term. The quality department may be the best candidate for assuming this responsibility because it is more likely to foster greater physician buy-in and acceptance of program objectives. If IT is to retain responsibility for the program, it will likely require the support of a strong analyst team.
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August 2014

Platform for induction and maintenance of transgene-free hiPSCs resembling ground state pluripotent stem cells.

Stem Cell Reports 2014 Mar 6;2(3):366-81. Epub 2014 Mar 6.

Fate Therapeutics, Inc., 3535 General Atomics Court, Suite 200, San Diego, CA 92121, USA.

Cell banking, disease modeling, and cell therapy applications have placed increasing demands on hiPSC technology. Specifically, the high-throughput derivation of footprint-free hiPSCs and their expansion in systems that allow scaled production remains technically challenging. Here, we describe a platform for the rapid, parallel generation, selection, and expansion of hiPSCs using small molecule pathway inhibitors in stage-specific media compositions. The platform supported efficient and expedited episomal reprogramming using just OCT4/SOX2/SV40LT combination (0.5%-4.0%, between days 12 and 16) in a completely feeder-free environment. The resulting hiPSCs are transgene-free, readily cultured, and expanded as single cells while maintaining a homogeneous and genomically stable pluripotent population. hiPSCs generated or maintained in the media compositions described exhibit properties associated with the ground state of pluripotency. The simplicity and robustness of the system allow for the high-throughput generation and rapid expansion of a uniform hiPSC product that is applicable to industrial and clinical-grade use.
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http://dx.doi.org/10.1016/j.stemcr.2014.01.014DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3964282PMC
March 2014