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1.
Mol Cell ; 75(2): 394-407.e5, 2019 07 25.
Article in English | MEDLINE | ID: mdl-31227230

ABSTRACT

The structural diversity of glycans on cells-the glycome-is vast and complex to decipher. Glycan arrays display oligosaccharides and are used to report glycan hapten binding epitopes. Glycan arrays are limited resources and present saccharides without the context of other glycans and glycoconjugates. We used maps of glycosylation pathways to generate a library of isogenic HEK293 cells with combinatorially engineered glycosylation capacities designed to display and dissect the genetic, biosynthetic, and structural basis for glycan binding in a natural context. The cell-based glycan array is self-renewable and reports glycosyltransferase genes required (or blocking) for interactions through logical sequential biosynthetic steps, which is predictive of structural glycan features involved and provides instructions for synthesis, recombinant production, and genetic dissection strategies. Broad utility of the cell-based glycan array is demonstrated, and we uncover higher order binding of microbial adhesins to clustered patches of O-glycans organized by their presentation on proteins.


Subject(s)
Genetic Engineering , Metabolic Networks and Pathways/genetics , Polysaccharides/chemistry , Proteins/genetics , Epitopes/genetics , Epitopes/immunology , Glycosylation , Glycosyltransferases/genetics , HEK293 Cells , Humans , Oligosaccharides/genetics , Polysaccharides/classification , Polysaccharides/genetics , Polysaccharides/immunology , Proteins/immunology
2.
Nature ; 554(7690): 62-68, 2018 02 01.
Article in English | MEDLINE | ID: mdl-29364867

ABSTRACT

The poor correlation of mutational landscapes with phenotypes limits our understanding of the pathogenesis and metastasis of pancreatic ductal adenocarcinoma (PDAC). Here we show that oncogenic dosage-variation has a critical role in PDAC biology and phenotypic diversification. We find an increase in gene dosage of mutant KRAS in human PDAC precursors, which drives both early tumorigenesis and metastasis and thus rationalizes early PDAC dissemination. To overcome the limitations posed to gene dosage studies by the stromal richness of PDAC, we have developed large cell culture resources of metastatic mouse PDAC. Integration of cell culture genomes, transcriptomes and tumour phenotypes with functional studies and human data reveals additional widespread effects of oncogenic dosage variation on cell morphology and plasticity, histopathology and clinical outcome, with the highest KrasMUT levels underlying aggressive undifferentiated phenotypes. We also identify alternative oncogenic gains (Myc, Yap1 or Nfkb2), which collaborate with heterozygous KrasMUT in driving tumorigenesis, but have lower metastatic potential. Mechanistically, different oncogenic gains and dosages evolve along distinct evolutionary routes, licensed by defined allelic states and/or combinations of hallmark tumour suppressor alterations (Cdkn2a, Trp53, Tgfß-pathway). Thus, evolutionary constraints and contingencies direct oncogenic dosage gain and variation along defined routes to drive the early progression of PDAC and shape its downstream biology. Our study uncovers universal principles of Ras-driven oncogenesis that have potential relevance beyond pancreatic cancer.


Subject(s)
Carcinoma, Pancreatic Ductal/genetics , Carcinoma, Pancreatic Ductal/pathology , Evolution, Molecular , Gene Dosage , Pancreatic Neoplasms/genetics , Pancreatic Neoplasms/pathology , Proto-Oncogene Proteins p21(ras)/genetics , Adaptor Proteins, Signal Transducing/genetics , Alleles , Animals , Carcinogenesis/genetics , Cell Cycle Proteins , Cyclin-Dependent Kinase Inhibitor p16/genetics , Disease Progression , Female , Genes, myc , Genes, p53 , Humans , Male , Mice , Mutation , NF-kappa B p52 Subunit/genetics , Neoplasm Metastasis/genetics , Nuclear Proteins/genetics , Phenotype , Phosphoproteins/genetics , Transcription Factors/genetics , Transcriptome/genetics , Transforming Growth Factor beta1/genetics , YAP-Signaling Proteins
3.
J Biol Chem ; 296: 100448, 2021.
Article in English | MEDLINE | ID: mdl-33617880

ABSTRACT

Advances in nuclease-based gene-editing technologies have enabled precise, stable, and systematic genetic engineering of glycosylation capacities in mammalian cells, opening up a plethora of opportunities for studying the glycome and exploiting glycans in biomedicine. Glycoengineering using chemical, enzymatic, and genetic approaches has a long history, and precise gene editing provides a nearly unlimited playground for stable engineering of glycosylation in mammalian cells to explore and dissect the glycome and its many biological functions. Genetic engineering of glycosylation in cells also brings studies of the glycome to the single cell level and opens up wider use and integration of data in traditional omics workflows in cell biology. The last few years have seen new applications of glycoengineering in mammalian cells with perspectives for wider use in basic and applied glycosciences, and these have already led to discoveries of functions of glycans and improved designs of glycoprotein therapeutics. Here, we review the current state of the art of genetic glycoengineering in mammalian cells and highlight emerging opportunities.


Subject(s)
Genetic Engineering , Animals , Gene Editing , Gene Expression Regulation , Gene Knockdown Techniques , Glycoproteins/metabolism , Glycosylation , Humans , Mammals , Polysaccharides/metabolism
4.
Eur J Nucl Med Mol Imaging ; 50(1): 115-129, 2022 Dec.
Article in English | MEDLINE | ID: mdl-36074156

ABSTRACT

PURPOSE: Pancreatic ductal adenocarcinoma (PDAC) is a molecularly heterogeneous tumor entity with no clinically established imaging biomarkers. We hypothesize that tumor morphology and physiology, including vascularity and perfusion, show variations that can be detected by differences in contrast agent (CA) accumulation measured non-invasively. This work seeks to establish imaging biomarkers for tumor stratification and therapy response monitoring in PDAC, based on this hypothesis. METHODS AND MATERIALS: Regional CA accumulation in PDAC was correlated with tumor vascularization, stroma content, and tumor cellularity in murine and human subjects. Changes in CA distribution in response to gemcitabine (GEM) were monitored longitudinally with computed tomography (CT) Hounsfield Units ratio (HUr) of tumor to the aorta or with magnetic resonance imaging (MRI) ΔR1 area under the curve at 60 s tumor-to-muscle ratio (AUC60r). Tissue analyses were performed on co-registered samples, including endothelial cell proliferation and cisplatin tissue deposition as a surrogate of chemotherapy delivery. RESULTS: Tumor cell poor, stroma-rich regions exhibited high CA accumulation both in human (meanHUr 0.64 vs. 0.34, p < 0.001) and mouse PDAC (meanAUC60r 2.0 vs. 1.1, p < 0.001). Compared to the baseline, in vivo CA accumulation decreased specifically in response to GEM treatment in a subset of human (HUr -18%) and mouse (AUC60r -36%) tumors. Ex vivo analyses of mPDAC showed reduced cisplatin delivery (GEM: 0.92 ± 0.5 mg/g, vs. vehicle: 3.1 ± 1.5 mg/g, p = 0.004) and diminished endothelial cell proliferation (GEM: 22.3% vs. vehicle: 30.9%, p = 0.002) upon GEM administration. CONCLUSION: In PDAC, CA accumulation, which is related to tumor vascularization and perfusion, inversely correlates with tumor cellularity. The standard of care GEM treatment results in decreased CA accumulation, which impedes drug delivery. Further investigation is warranted into potentially detrimental effects of GEM in combinatorial therapy regimens.


Subject(s)
Carcinoma, Pancreatic Ductal , Pancreatic Neoplasms , Humans , Mice , Animals , Cisplatin/therapeutic use , Xenograft Model Antitumor Assays , Carcinoma, Pancreatic Ductal/diagnostic imaging , Carcinoma, Pancreatic Ductal/drug therapy , Carcinoma, Pancreatic Ductal/pathology , Pancreatic Neoplasms/diagnostic imaging , Pancreatic Neoplasms/drug therapy , Pancreatic Neoplasms/pathology , Neovascularization, Pathologic/diagnostic imaging , Neovascularization, Pathologic/drug therapy , Biomarkers , Tomography, X-Ray Computed , Magnetic Resonance Imaging , Tomography , Cell Line, Tumor , Gemcitabine , Pancreatic Neoplasms
5.
Br J Dermatol ; 187(2): 178-187, 2022 08.
Article in English | MEDLINE | ID: mdl-35152404

ABSTRACT

BACKGROUND: Clinical practice guidelines (CPGs) developed with rigorous methods can help optimize clinical care for patients with psoriasis. OBJECTIVES: To conduct an updated systematic review and comprehensive critical appraisal of global psoriasis CPGs. METHODS: A search of MEDLINE and Embase for psoriasis CPGs published between 1 January 2015 and 31 March 2021 was performed. Other guideline repositories were also searched for relevant CPGs. Descriptive analysis was conducted to summarize included guidelines. Three critical appraisal tools were used to assess the quality of included CPGs: the Appraisal of Guidelines for Research and Evaluation (AGREE) II instrument, Lenzer et al.'s red flags, and the US Institute of Medicine's (IOM) criteria of trustworthiness. RESULTS: We included 33 psoriasis CPGs, with 25 openly accessible. Most CPGs were from high sociodemographic index countries in North America and Europe. Five CPGs received 'excellent quality' appraisals across all six AGREE II domains. Stakeholder involvement, rigour of development and applicability were the three domains with the lowest appraisal scores for AGREE II. Twenty-two CPGs raised at least one red flag indicative of potential bias. By the IOM's standards, external review of the guideline draft prior to publication and clear updating procedures were most often not addressed by guidelines, and only three CPGs were assessed as having higher overall trustworthiness. CONCLUSIONS: Most psoriasis guidelines were unable to consistently demonstrate high quality across multiple appraisal tools. The EuroGuiDerm guideline on the systemic treatment of psoriasis vulgaris was the only CPG to receive 'excellent quality' across all six AGREE II domains, to raise no Lenzer's red flags, and to have higher trustworthiness by IOM criteria.


Subject(s)
Dermatology , Psoriasis , Academies and Institutes , Europe , Humans , North America , Practice Guidelines as Topic , Psoriasis/diagnosis , Psoriasis/therapy
6.
Epilepsy Behav ; 126: 108462, 2022 01.
Article in English | MEDLINE | ID: mdl-34896784

ABSTRACT

PURPOSE: No studies have examined the relationship between the intensity of facial emotion expression and theory of mind (ToM) ability in people with epilepsy. This study aimed to explore facial emotion recognition in a group of patients with frontal (FLE) or temporal lobe epilepsy (TLE) and its relationship with the intensities of perceived facial emotion expressions, ToM, and social functioning. METHODS: Twenty-six patients with FLE or TLE and 30 matched controls were included in the study. All participants completed the facial emotion recognition test, Faux Pas Recognition (FPR) test measuring advanced ToM, Symptom Checklist-90-Revised, Social and Occupational Functioning Scale for Epilepsy (SOFSE), and background neuropsychological tests. RESULTS: The patient group was significantly worse than the control group in recognizing facial expressions of negative emotions, particularly for medium-intensity facial expression of fear. There was no significant difference between the groups in recognizing high-intensity fear facial expressions. The scores of FPR (overall and affective ToMs) in the patient group were significantly lower than those in the control group. Additionally, the facial emotion recognition was significantly associated with the total score of FPR, and the FPR total score remarkably correlated with the Communication subscale score of the SOFSE. CONCLUSIONS: Patients with FLE or TLE had impaired ability to recognize medium-intensity facial expressions of fear. Moreover, patients' ToM deficit significantly correlated not only with their emotion recognition problem but also with their social-communicative competence. Nevertheless, we also found that increasing the intensity of expression can improve the accuracy of emotion recognition in patients with epilepsy. These findings may provide considerations for further longitudinal studies and interventions on the social difficulties of people with epilepsy.


Subject(s)
Epilepsy, Temporal Lobe , Theory of Mind , Emotions , Epilepsy, Temporal Lobe/psychology , Facial Expression , Humans , Neuropsychological Tests
7.
Cell Mol Life Sci ; 78(21-22): 6963-6978, 2021 Nov.
Article in English | MEDLINE | ID: mdl-34586443

ABSTRACT

The endogenous chemokines CCL19 and CCL21 signal via their common receptor CCR7. CCL21 is the main lymph node homing chemokine, but a weak chemo-attractant compared to CCL19. Here we show that the 41-amino acid positively charged peptide, released through C-terminal cleavage of CCL21, C21TP, boosts the immune cell recruiting activity of CCL21 by up to 25-fold and the signaling activity via CCR7 by ~ 100-fold. Such boosting is unprecedented. Despite the presence of multiple basic glycosaminoglycan (GAG) binding motifs, C21TP boosting of CCL21 signaling does not involve interference with GAG mediated cell-surface retention. Instead, boosting is directly dependent on O-glycosylations in the CCR7 N-terminus. As dictated by the two-step binding model, the initial chemokine binding involves interaction of the chemokine fold with the receptor N-terminus, followed by insertion of the chemokine N-terminus deep into the receptor binding pocket. Our data suggest that apart from a role in initial chemokine binding, the receptor N-terminus also partakes in a gating mechanism, which could give rise to a reduced ligand activity, presumably through affecting the ligand positioning. Based on experiments that support a direct interaction of C21TP with the glycosylated CCR7 N-terminus, we propose that electrostatic interactions between the positively charged peptide and sialylated O-glycans in CCR7 N-terminus may create a more accessible version of the receptor and thus guide chemokine docking to generate a more favorable chemokine-receptor interaction, giving rise to the peptide boosting effect.


Subject(s)
Chemokine CCL21/metabolism , Dendritic Cells/metabolism , Lymph Nodes/metabolism , Receptors, CCR7/metabolism , Receptors, Lymphocyte Homing/metabolism , Signal Transduction/physiology , Animals , CHO Cells , Cells, Cultured , Cricetulus , Glycosylation , Humans , Ligands , Peptides/metabolism , Protein Binding/physiology , Static Electricity
8.
J Dtsch Dermatol Ges ; 20(2): 157-166, 2022 02.
Article in English | MEDLINE | ID: mdl-35088518

ABSTRACT

BACKGROUND: Some clinical trials found that cyclooxygenase-2 (COX-2) inhibitor use lowered the risk of skin cancer in high-risk groups. PATIENTS AND METHODS: To determine whether COX-2 inhibitor use is associated with lower risk of basal cell carcinoma (BCC), cutaneous squamous cell carcinoma (cSCC), and melanoma, we analyzed COX-2 inhibitor use and risk of skin cancer based on three prospective cohort studies, the Nurses' Health Study (NHS), NHS II, and the Health Professionals Follow-up Study, including 153,882 participants. Multivariable hazard ratios (HRs) and 95 % confidence intervals (CIs) for the association of COX-2 inhibitor use with risk of BCC, cSCC, and melanoma were estimated using Cox proportional hazards models. We pooled the results using a fixed effects model. RESULTS: 16,142 BCC, 1,973 cSCC, and 631 melanoma cases were documented. Ever vs. never use of COX-2 inhibitor was associated with a modestly increased risk of BCC (multivariable HR 1.09, 95 % CI 1.05-1.14). The hazard ratio was similar for cSCC (multivariable HR 1.12, 95 % CI 1.00-1.27) and melanoma (multivariable HR 1.10, 95 % CI 0.89-1.38), but was not statistically significant. CONCLUSIONS: Ever use of COX-2 inhibitor was not associated with a decreased skin cancer risk but was instead associated with a modest, increased risk of BCC.


Subject(s)
Carcinoma, Basal Cell , Carcinoma, Squamous Cell , Skin Neoplasms , Carcinoma, Basal Cell/chemically induced , Carcinoma, Basal Cell/epidemiology , Carcinoma, Basal Cell/prevention & control , Carcinoma, Squamous Cell/chemically induced , Carcinoma, Squamous Cell/epidemiology , Carcinoma, Squamous Cell/prevention & control , Cyclooxygenase 2 Inhibitors/therapeutic use , Follow-Up Studies , Humans , Prospective Studies , Risk Factors , Skin Neoplasms/chemically induced , Skin Neoplasms/epidemiology , Skin Neoplasms/prevention & control
9.
Glycobiology ; 31(5): 624-635, 2021 06 03.
Article in English | MEDLINE | ID: mdl-33403394

ABSTRACT

Cell surface glycosylation has been known as an important modification process that can be targeted and manipulated by malignant cells to escape from host immunosurveillance. We previously showed that the blood group branched I antigen on the leukemia cell surface can regulate the cell susceptibility against natural killer (NK) cell-mediated cytotoxicity through interfering target-NK interaction. In this work, we first identified N-linkage as the major glycosylation linkage type for branched I glycan formation on leukemia cells, and this linkage was responsible for cell sensitivity against therapeutic NK-92MI targeting. Secondly, by examining different leukemia cell surface death receptors, we showed death receptor Fas had highest expressions in both Raji and TF-1a cells. Mutations on two Fas extracellular N-linkage sites (118 and 136) for glycosylation impaired activation of Fas-mediated apoptosis during NK-92MI cytotoxicity. Last, we found that the surface I antigen expression levels enable leukemia cells to respond differently against NK-92MI targeting. In low I antigen expressing K-562 cell, reduction of I antigen presence greatly reduced leukemia cell susceptibility against NK-92MI targeting. But in other high I antigen expressing leukemia cells, similar reduction in I antigen expression did not affect cell susceptibility.


Subject(s)
Cytotoxicity, Immunologic/immunology , Histocompatibility Antigens Class I/immunology , Killer Cells, Natural/immunology , fas Receptor/immunology , Apoptosis/immunology , Cells, Cultured , Glycosylation , Histocompatibility Antigens Class I/genetics , Humans , Mutation , fas Receptor/genetics
10.
Curr Issues Mol Biol ; 43(1)2021 Apr 27.
Article in English | MEDLINE | ID: mdl-33925358

ABSTRACT

Colorectal cancer (CRC) has the fourth-highest incidence of all cancer types, and its incidence has steadily increased in the last decade. The general transcription factor III (GTF3) family, comprising GTF3A, GTF3B, GTF3C1, and GTFC2, were stated to be linked with the expansion of different types of cancers; however, their messenger (m)RNA expressions and prognostic values in colorectal cancer need to be further investigated. To study the transcriptomic expression levels of GTF3 gene members in colorectal cancer in both cancerous tissues and cell lines, we first performed high-throughput screening using the Oncomine, GEPIA, and CCLE databases. We then applied the Prognoscan database to query correlations of their mRNA expressions with the disease-specific survival (DSS), overall survival (OS), and disease-free survival (DFS) status of the colorectal cancer patient. Furthermore, proteomics expressions of GTF3 family members in clinical colorectal cancer specimens were also examined using the Human Protein Atlas. Finally, genomic alterations of GTF3 family gene expressions in colorectal cancer and their signal transduction pathways were studied using cBioPortal, ClueGO, CluePedia, and MetaCore platform. Our findings revealed that GTF3 family members' expressions were significantly correlated with the cell cycle, oxidative stress, WNT/ß-catenin signaling, Rho GTPases, and G-protein-coupled receptors (GPCRs). Clinically, high GTF3A and GTF3B expressions were significantly correlated with poor prognoses in colorectal cancer patients. Collectively, our study declares that GTF3A was overexpressed in cancer tissues and cell lines, particularly colorectal cancer, and it could possibly step in as a potential prognostic biomarker.


Subject(s)
Colorectal Neoplasms/pathology , Computational Biology/methods , Gene Expression Regulation, Neoplastic , Muscle Proteins/genetics , Nuclear Proteins/genetics , TATA-Binding Protein Associated Factors/genetics , Trans-Activators/genetics , Wnt Signaling Pathway , Biomarkers, Tumor/genetics , Biomarkers, Tumor/metabolism , Cell Division , Colorectal Neoplasms/genetics , Colorectal Neoplasms/metabolism , Databases, Genetic , Databases, Protein , Humans , Muscle Proteins/metabolism , Nuclear Proteins/metabolism , Prognosis , TATA-Binding Protein Associated Factors/metabolism , Trans-Activators/metabolism
11.
Nat Methods ; 15(11): 881-888, 2018 11.
Article in English | MEDLINE | ID: mdl-30104636

ABSTRACT

Glycosaminoglycans (GAGs) are essential polysaccharides in normal physiology and disease. However, understanding of the contribution of specific GAG structures to specific biological functions is limited, largely because of the great structural heterogeneity among GAGs themselves, as well as technical limitations in the structural characterization and chemical synthesis of GAGs. Here we describe a cell-based method to produce and display distinct GAGs with a broad repertoire of modifications, a library we refer to as the GAGOme. By using precise gene editing, we engineered a large panel of Chinese hamster ovary cells with knockout or knock-in of the genes encoding most of the enzymes involved in GAG biosynthesis, to generate a library of isogenic cell lines that differentially display distinct GAG features. We show that this library can be used for cell-based binding assays, recombinant expression of proteoglycans with distinct GAG structures, and production of distinct GAG chains on metabolic primers that may be used for the assembly of GAG glycan microarrays.


Subject(s)
Gene Expression Regulation , Gene Library , Glycomics/methods , Glycosaminoglycans/metabolism , Proteoglycans/metabolism , Animals , CHO Cells , Carrier Proteins/genetics , Carrier Proteins/metabolism , Cricetinae , Cricetulus
12.
Toxicol Pathol ; 49(6): 1206-1228, 2021 08.
Article in English | MEDLINE | ID: mdl-34259102

ABSTRACT

The histopathology slide seminar "Classic Examples in Toxicologic Pathology XXVII" was held on February 21 and 22, 2020, at the Department of Pathology at the University of Veterinary Medicine in Hannover, Germany, with joint organization by the European Society of Toxicologic Pathology. The goal of this annual seminar is to present and discuss classical and actual cases of toxicologic pathology. This article summarizes the presentations given during the seminar, including images of representative lesions. Ten actual and classical cases of toxicologic pathology, mostly induced by a test article, were presented. These included small intestine pathology and transcriptomics induced by a γ-secretase modulator, liver findings in nonhuman primates induced by gene therapy, drug-induced neutropenia in dogs, device-induced growth plate lesions, polycystic lesions in CAR/PXR double knockout mice, inner ear lesions in transgenic mice, findings in Beagle dogs induced by an inhibitor of the myeloid leukemia cell differentiation protein MCL1, findings induced by a monovalent fibroblast growth factor receptor 1 antagonist, kidney lesions induced by a mammalian target of rapamycin inhibitor in combination therapy, and findings in mutation-specific drugs.


Subject(s)
Amyloid Precursor Protein Secretases , Pathology , Animals , Dogs , Fibroblast Growth Factor-23 , Genetic Therapy , Growth Plate , Mice , Mice, Knockout , Mice, Transgenic
13.
Environ Toxicol ; 36(6): 1080-1089, 2021 Jun.
Article in English | MEDLINE | ID: mdl-33522686

ABSTRACT

INTRODUCTION: Prostate cancer has significant mortality and metastasis rate in the male. Unfortunately, effective treatment for patients with advanced prostate cancer is still lacking. Verbascoside, a phenylethanoid glycoside, displays various pharmacological properties, such as the anti-cancer activities. The present study aimed to evaluate the effects of purified verbascoside on human prostate cancer and the associated molecular mechanisms. MATERIALS AND METHODS: The human prostate cancer cell lines, Du-145 and PC-3, were treated with various concentrations of verbascoside (0.1, 1, 10 µM) for 24 h followed by the examination of cell viability using MTT and trypan blue exclusion assays. Cell migration and invasion capacities were assessed by wound healing assay and transwell system. Western blot and immunofluorescence staining were used to detect the expression of epithelial-mesenchymal transition (EMT)-associated factors, components of transforming growth factor (TGF-ß)/Smad signaling, and high-mobility group box (HMGB)/receptor for advanced glycation end-products (RAGE) axis. RESULTS: Verbascoside treatment significantly inhibited cell proliferation, migration, and invasion abilities of Du-145 and PC-3 cells. We showed that verbascoside decreased the expression of EMT promotors, Snail and Slug, and increased the expression of E-cadherin. Moreover, the expression level of alpha-smooth muscle actin was downregulated by verbascoside as well. Besides, we found that the TGF-ß pathway was suppressed, which was demonstrated by the diminished expression of type I and II TGF-ß receptors and phosphorylated Smad2/3 along with the upregulated Smad7. Our data suggested that this downregulation of TGF-ß signaling was mediated by repression of HMGB 1 (HMGB1)/RAGE axis. CONCLUSION: Verbascoside mitigated the cell proliferation and aggressiveness of prostate cancer via downregulation of TGF-ß-associated EMT progression through HMGB1/RAGE suppression. Collectively, our findings revealed that verbascoside may be a beneficial dietary supplement for prostate cancer patients.


Subject(s)
HMGB1 Protein , Prostatic Neoplasms , Cell Line, Tumor , Cell Movement , Epithelial-Mesenchymal Transition , Glucosides , Humans , Male , Phenols , Receptor for Advanced Glycation End Products , Transforming Growth Factor beta , Transforming Growth Factor beta1
14.
Immunology ; 160(1): 38-51, 2020 05.
Article in English | MEDLINE | ID: mdl-32027025

ABSTRACT

First discovered on the natural killer (NK) cell, the cell surface inhibitory receptor sialic acid-binding immunoglobulin-like lectin-7 (Siglec-7) is known for regulating many important biological activities. However, the detail regulatory mechanism for Siglec-7 expression in NK cells currently remains unclear. In this study, we aimed to investigate how cell surface Siglec-7 expression is regulated and found that, in both NK cell lines and peripheral NK cells, transcription was the main regulatory step. Furthermore, when NK-92MI and peripheral NK cells were treated with DNA methyltransferase (DNMT) inhibitor, the CpG island, with 9 CpG sites, in 5' Siglec-7 promoter became noticeably hypomethylated, and Siglec-7 expression increased in both RNA transcript and surface protein. Within this CpG island, we identified both CpG 8 and CpG 9 as two key regulators responsible for Siglec-7 expression. Additionally, by using histone deacetylases (HDAC) inhibitor, butyric acid, we showed that Siglec-7 expression was also subjected to the histone modification. And a combined treatment with both 5-azacytidine and butyric acid showed an additive effect on Siglec-7 transcript expression in peripheral NK cells.


Subject(s)
Antigens, Differentiation, Myelomonocytic/genetics , Epigenesis, Genetic/immunology , Killer Cells, Natural/immunology , Lectins/genetics , Antigens, Differentiation, Myelomonocytic/metabolism , Azacitidine/pharmacology , Butyric Acid/pharmacology , Cell Line , CpG Islands/genetics , DNA Methylation/drug effects , DNA Methylation/immunology , Epigenesis, Genetic/drug effects , Histone Code/drug effects , Histone Deacetylase Inhibitors/pharmacology , Histone Deacetylases/metabolism , Humans , Killer Cells, Natural/drug effects , Killer Cells, Natural/metabolism , Lectins/metabolism , Promoter Regions, Genetic/genetics , RNA-Seq , Transcription, Genetic/drug effects , Transcription, Genetic/immunology
15.
Nature ; 507(7490): 78-80, 2014 Mar 06.
Article in English | MEDLINE | ID: mdl-24522533

ABSTRACT

IRAS 04368+2557 is a solar-type (low-mass) protostar embedded in a protostellar core (L1527) in the Taurus molecular cloud, which is only 140 parsecs away from Earth, making it the closest large star-forming region. The protostellar envelope has a flattened shape with a diameter of a thousand astronomical units (1 AU is the distance from Earth to the Sun), and is infalling and rotating. It also has a protostellar disk with a radius of 90 AU (ref. 6), from which a planetary system is expected to form. The interstellar gas, mainly consisting of hydrogen molecules, undergoes a change in density of about three orders of magnitude as it collapses from the envelope into the disk, while being heated from 10 kelvin to over 100 kelvin in the mid-plane, but it has hitherto not been possible to explore changes in chemical composition associated with this collapse. Here we report that the unsaturated hydrocarbon molecule cyclic-C3H2 resides in the infalling rotating envelope, whereas sulphur monoxide (SO) is enhanced in the transition zone at the radius of the centrifugal barrier (100 ± 20 AU), which is the radius at which the kinetic energy of the infalling gas is converted to rotational energy. Such a drastic change in chemistry at the centrifugal barrier was not anticipated, but is probably caused by the discontinuous infalling motion at the centrifugal barrier and local heating processes there.

16.
J Am Acad Dermatol ; 80(5): 1332-1343, 2019 May.
Article in English | MEDLINE | ID: mdl-30590074

ABSTRACT

BACKGROUND: An overview of mortality risk associated with psoriasis is lacking. OBJECTIVE: To perform a systematic review and meta-analysis of mortality risk in psoriasis. METHODS: We included studies reporting all-cause or cause-specific mortality risk estimates in psoriasis patients compared with general population or subjects free of psoriasis. We calculated pooled relative risks (RRs) and 95% confidence intervals (CIs). RESULTS: We included 12 studies. The pooled RRs for all-cause mortality were 1.21 (95% CI 1.14-1.28) in psoriasis, 1.13 (95% CI 1.09-1.16) in mild psoriasis, and 1.52 (95% CI 1.35-1.71) in severe psoriasis. The pooled RRs for cardiovascular mortality were 1.15 (95% CI 1.09-1.21) in psoriasis, 1.05 (95% CI 0.92-1.20) in mild psoriasis, and 1.38 (95% CI 1.09-1.74) in severe psoriasis. For noncardiovascular causes, mortality risk from liver disease, kidney disease, and infection was significantly increased in psoriasis, regardless of disease severity. The mortality risk in liver and kidney disease was the highest. There was also a significantly increased mortality risk associated with neoplasms in severe psoriasis patients and chronic lower respiratory disease in all and mild psoriasis patients. LIMITATIONS: Although associations were consistent, their magnitude was heterogenous. CONCLUSION: Psoriasis is associated with an increased risk for mortality from all causes (in a dose-response manner with disease severity) and from several specific causes.


Subject(s)
Infections/mortality , Kidney Diseases/mortality , Liver Diseases/mortality , Neoplasms/mortality , Psoriasis/mortality , Respiratory Tract Diseases/mortality , Cause of Death , Comorbidity , Humans , Risk Assessment , Severity of Illness Index
17.
Glycobiology ; 28(5): 295-305, 2018 05 01.
Article in English | MEDLINE | ID: mdl-29315387

ABSTRACT

Over 200 glycosyltransferases are involved in the orchestration of the biosynthesis of the human glycome, which is comprised of all glycan structures found on different glycoconjugates in cells. The glycome is vast, and despite advancements in analytic strategies it continues to be difficult to decipher biological roles of glycans with respect to specific glycan structures, type of glycoconjugate, particular glycoproteins, and distinct glycosites on proteins. In contrast to this, the number of glycosyltransferase genes involved in the biosynthesis of the human glycome is manageable, and the biosynthetic roles of most of these enzymes are defined or can be predicted with reasonable confidence. Thus, with the availability of the facile CRISPR/Cas9 gene editing tool it now seems easier to approach investigation of the functions of the glycome through genetic dissection of biosynthetic pathways, rather than by direct glycan analysis. However, obstacles still remain with design and validation of efficient gene targeting constructs, as well as with the interpretation of results from gene targeting and the translation of gene function to glycan structures. This is especially true for glycosylation steps covered by isoenzyme gene families. Here, we present a library of validated high-efficiency gRNA designs suitable for individual and combinatorial targeting of the human glycosyltransferase genome together with a global view of the predicted functions of human glycosyltransferases to facilitate and guide gene targeting strategies in studies of the human glycome.


Subject(s)
CRISPR-Cas Systems/genetics , Gene Library , Glycosyltransferases/genetics , RNA, Guide, Kinetoplastida/genetics , Glycosyltransferases/metabolism , HEK293 Cells , Humans , RNA, Guide, Kinetoplastida/metabolism , Reproducibility of Results
18.
Glycobiology ; 28(7): 542-549, 2018 07 01.
Article in English | MEDLINE | ID: mdl-29596681

ABSTRACT

Precise gene editing technologies are providing new opportunities to stably engineer host cells for recombinant production of therapeutic glycoproteins with different glycan structures. The glycosylation of recombinant therapeutics has long been a focus for both quality and consistency of products and for optimizing and improving pharmacokinetic properties as well as bioactivity. Structures of glycans on therapeutic glycoproteins are important for circulation, biodistribution and bioactivity. In particular, the latter has been demonstrated for therapeutic IgG1 antibodies where the core α1,6Fucose on the conserved N-glycan at Asn297 have remarkable dampening effects on antibody effector functions. We previously explored precise gene engineering and design options for N-glycosylation in CHO cells, and here we focus on engineering options possible for N-glycans on human IgG1. We demonstrate stable precise gene engineering of rather homogenous biantennary N-glycans with and without galactose (G0F, G2F) as well as the α2,6-linked monosialylated (G2FS1) glycoform. We were unable to introduce substantial disialylated glycoforms. Instead we engineered a novel monoantennary homogeneous N-glycan design with complete α2,6-linked sialic acid capping. All N-glycoforms may be engineered with and without core α1,6Fucose. The stably engineered design options enable production of human IgG antibodies with an array of distinct glycoforms for testing and selection of optimal design for different therapeutic applications.


Subject(s)
Gene Editing/methods , Immunoglobulin G/genetics , Protein Processing, Post-Translational , Animals , CHO Cells , Cricetinae , Cricetulus , Glycosylation , Humans , Immunoglobulin G/chemistry , Immunoglobulin G/metabolism , Polysaccharides/metabolism
20.
J Am Acad Dermatol ; 79(2): 252-257.e6, 2018 Aug.
Article in English | MEDLINE | ID: mdl-29698709

ABSTRACT

BACKGROUND: Red and processed meat consumption has been associated with increased risk for several cancers, but the association with cutaneous melanoma risk has been inconclusive. OBJECTIVE: To investigate the association between red and processed meat intake and melanoma risk. METHODS: Dietary information was assessed by using food frequency questionnaires in 2 prospective cohorts: 75,263 women from the Nurses' Health Study (1984-2010) and 48,523 men from the Health Professionals Follow-up Study (1986-2010). Melanoma cases were confirmed by reviewing pathology records. Pooled multivariable hazard ratios and 95% confidence intervals were estimated by using Cox proportional hazards models. RESULTS: A total of 679 female and 639 male melanoma cases were documented during follow-up. Red and processed meat intake was inversely associated with melanoma risk (P = .002 for trend); the pooled hazard ratios (95% confidence intervals) of the 2 cohorts were 1.00 (reference), 1.00 (0.87-1.14), 0.98 (0.86-1.13), 0.89 (0.77-1.02), and 0.81 (0.70-0.95) for increasing quintiles of intake. LIMITATIONS: Findings might have limited generalizability, considering that the cohorts were limited to white health professionals. CONCLUSION: Red and processed meat intake was inversely associated with melanoma risk in these 2 cohorts.


Subject(s)
Diet/adverse effects , Meat Products/adverse effects , Melanoma/epidemiology , Red Meat/adverse effects , Skin Neoplasms/epidemiology , White People/statistics & numerical data , Adult , Female , Humans , Male , Melanoma/ethnology , Middle Aged , Proportional Hazards Models , Prospective Studies , Risk Factors , Skin Neoplasms/ethnology , Surveys and Questionnaires , Melanoma, Cutaneous Malignant
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