Tissue invasion and metastasis: Molecular, biological and clinical perspectives

Cancer is a key health issue across the world, causing substantial patient morbidity and mortality. Patient prognosis is tightly linked with metastatic dissemination of the disease to distant sites, with metastatic diseases accounting for a vast percentage of cancer patient mortality. While advances in this area have been made, the process of cancer metastasis and the factors governing cancer spread and establishment at secondary locations is still poorly understood. The current article summarizes recent progress in this area of research, both in the understanding of the underlying biological processes and in the therapeutic strategies for the management of metastasis. This review lists the disruption of E-cadherin and tight junctions, key signaling pathways, including urokinase type plasminogen activator (uPA), phosphatidylinositol 3-kinase/v-akt murine thymoma viral oncogene (PI3K/AKT), focal adhesion kinase (FAK), β-catenin/zinc finger E-box binding homeobox 1 (ZEB-1) and transforming growth factor beta (TGF-β), together with inactivation of activator protein-1 (AP-1) and suppression of matrix metalloproteinase-9 (MMP-9) activity as key targets and the use of phytochemicals, or natural products, such as those from Agaricus blazei, Albatrellus confluens, Cordyceps militaris, Ganoderma lucidum, Poria cocos and Silybum marianum, together with diet derived fatty acids gamma linolenic acid (GLA) and eicosapentanoic acid (EPA) and inhibitory compounds as useful approaches to target tissue invasion and metastasis as well as other hallmark areas of cancer. Together, these strategies could represent new, inexpensive, low toxicity strategies to aid in the management of cancer metastasis as well as having holistic effects against other cancer hallmarks.

Atopic Dermatitis Is an IL-13-Dominant Disease with Greater Molecular Heterogeneity Compared to Psoriasis

Atopic dermatitis (AD) affects up to 20% of children and adults worldwide. To gain a deeper understanding of the pathophysiology of AD, we conducted a large-scale transcriptomic study of AD with deeply sequenced RNA-sequencing samples using long (126-bp) paired-end reads. In addition to the comparisons against previous transcriptomic studies, we conducted in-depth analysis to obtain a high-resolution view of the global architecture of the AD transcriptome and contrasted it with that of psoriasis from the same cohort. By using 147 RNA samples in total, we found striking correlation between dysregulated genes in lesional psoriasis and lesional AD skin with 81% of AD dysregulated genes being shared with psoriasis. However, we described disease-specific molecular and cellular features, with AD skin showing dominance of IL-13 pathways, but with near undetectable IL-4 expression. We also demonstrated greater disease heterogeneity and larger proportion of dysregulated long noncoding RNAs in AD, and illustrated the translational impact, including skin-type classification and drug-target prediction. This study is by far the largest study comparing the AD and psoriasis transcriptomes using RNA sequencing and demonstrating the shared inflammatory components, as well as specific discordant cytokine signatures of these two skin diseases.

Thrombocytopenic coagulopathy (Kasabach-Merritt phenomenon) is associated with Kaposiform hemangioendothelioma and not with common infantile hemangioma

Children with a large vascular tumor and associated Kasabach-Merritt coagulopathy respond inconsistently to therapy and have a high mortality rate. For this reason, we undertook a retrospective study of 21 such patients, and focused on clinical, radiographic, and histopathologic features. The male to female ratio was 1:1.6. Tumor was noted at birth in 50 percent of patients; the remainder appeared throughout infancy. The location was cervicofacial (n = 2), shoulder/upper limb (n = 4), trunk including retroperitoneum (n = 11), and lower limb (n = 4). These tumors grew rapidly to large size and were characterized by cutaneous purpura, edema, and an advancing ecchymotic margin. In contrast to common hemangioma, magnetic resonance imaging showed diffuse enhancement with ill-defined margins, cutaneous thickening, stranding of subcutaneous fat, hemosiderin deposits, and small feeding and draining vessels. All tumors were Kaposiform hemangioendothelioma (KHE); none were infantile hemangioma. Light microscopy showed irregular lobules or sheets of poorly formed, small vascular channels infiltrating and entrapping normal tissues. Characteristic features included spindle-shaped endothelial cells, diminished pericytes and mast cells, microthrombi, and hemosiderin deposits. Wide endothelial intercellular gaps and incomplete basement membranes were seen by electron microscopy. Dilated, hyperplastic, lymphaticoid channels were prominent in one tumor. KHE in 14 infants was treated with interferon alpha-2a: 6 had accelerated regression; 2 had stabilization of growth; and 6 evidenced no response. The mortality rate was 24 percent (5 of 21); this included three infants with retroperitoneal KHE. Kasabach-Merritt phenomenon does not occur with common hemangioma. Rather it is associated with the more aggressive KHE and rarely with other vascular neoplasms. Variable response to current pharmacologic therapy underscores our inadequate knowledge of the pathogenesis of thrombocytopenia in KHE.

Complex asparagine-linked oligosaccharides are required for morphogenic events during post-implantation development

Complex asparagine (N)-linked oligosaccharides appear late in phylogeny and are highly regulated in vertebrates. Variations in these structures are found on the majority of cell-surface and secreted proteins. Complex N-linked oligosaccharide biosynthesis is initiated in the Golgi apparatus by the action of Mgat-1-encoded UDP-N-acetylglucosamine:alpha-3-D- mannoside beta-1,2-N-acetylglucosaminyltransferase I (GlcNAc-TI). To determine if these structures govern ontogenic processes in mammals, mouse embryos were generated that lacked a functional Mgat-1 gene. Inactivation of both Mgat-1 alleles produced deficiencies in GlcNAc-TI activity and complex N-linked oligosaccharides. Embryonic lethality occurred by day 10.5, thus establishing that complex N-linked oligosaccharides are required during post-implantation development. Remarkably, embryonic development proceeded into day 9 with the differentiation of multiple cell types. Complex N-linked oligosaccharides are important for morphogenic processes as neural tube formation, vascularization and the determination of left-right body plan asymmetry were impaired in the absence of a functional Mgat-1 gene.

X-ray crystal structure of rabbit N-acetylglucosaminyltransferase I: catalytic mechanism and a new protein superfamily

N:-acetylglucosaminyltransferase I (GnT I) serves as the gateway from oligomannose to hybrid and complex N:-glycans and plays a critical role in mammalian development and possibly all metazoans. We have determined the X-ray crystal structure of the catalytic fragment of GnT I in the absence and presence of bound UDP-GlcNAc/Mn(2+) at 1.5 and 1.8 A resolution, respectively. The structures identify residues critical for substrate binding and catalysis and provide evidence for similarity, at the mechanistic level, to the deglycosylation step of retaining beta-glycosidases. The structuring of a 13 residue loop, resulting from UDP-GlcNAc/Mn(2+) binding, provides an explanation for the ordered sequential 'Bi Bi' kinetics shown by GnT I. Analysis reveals a domain shared with Bacillus subtilis glycosyltransferase SpsA, bovine beta-1,4-galactosyl transferase 1 and Escherichia coli N:-acetylglucosamine-1-phosphate uridyltransferase. The low sequence identity, conserved fold and related functional features shown by this domain define a superfamily whose members probably share a common ancestor. Sequence analysis and protein threading show that the domain is represented in proteins from several glycosyltransferase families.

Photosensitivity and type I IFN responses in cutaneous lupus are driven by epidermal-derived interferon kappa

OBJECTIVE

Skin inflammation and photosensitivity are common in patients with cutaneous lupus erythematosus (CLE) and systemic lupus erythematosus (SLE), yet little is known about the mechanisms that regulate these traits. Here we investigate the role of interferon kappa (IFN-κ) in regulation of type I interferon (IFN) and photosensitive responses and examine its dysregulation in lupus skin.

METHODS

mRNA expression of type I IFN genes was analysed from microarray data of CLE lesions and healthy control skin. Similar expression in cultured primary keratinocytes, fibroblasts and endothelial cells was analysed via RNA-seq. IFNK knock-out (KO) keratinocytes were generated using CRISPR/Cas9. Keratinocytes stably overexpressing IFN-κ were created via G418 selection of transfected cells. IFN responses were assessed via phosphorylation of STAT1 and STAT2 and qRT-PCR for IFN-regulated genes. Ultraviolet B-mediated apoptosis was analysed via TUNEL staining. In vivo protein expression was assessed via immunofluorescent staining of normal and CLE lesional skin.

RESULTS

IFNK is one of two type I IFNs significantly increased (1.5-fold change, false discovery rate (FDR) q<0.001) in lesional CLE skin. Gene ontology (GO) analysis showed that type I IFN responses were enriched (FDR=6.8×10-04) in keratinocytes not in fibroblast and endothelial cells, and this epithelial-derived IFN-κ is responsible for maintaining baseline type I IFN responses in healthy skin. Increased levels of IFN-κ, such as seen in SLE, amplify and accelerate responsiveness of epithelia to IFN-α and increase keratinocyte sensitivity to UV irradiation. Notably, KO of IFN-κ or inhibition of IFN signalling with baricitinib abrogates UVB-induced apoptosis.

CONCLUSION

Collectively, our data identify IFN-κ as a critical IFN in CLE pathology via promotion of enhanced IFN responses and photosensitivity. IFN-κ is a potential novel target for UVB prophylaxis and CLE-directed therapy.

Analysis of long non-coding RNAs highlights tissue-specific expression patterns and epigenetic profiles in normal and psoriatic skin

BACKGROUND

Although analysis pipelines have been developed to use RNA-seq to identify long non-coding RNAs (lncRNAs), inference of their biological and pathological relevance remains a challenge. As a result, most transcriptome studies of autoimmune disease have only assessed protein-coding transcripts.

RESULTS

We used RNA-seq data from 99 lesional psoriatic, 27 uninvolved psoriatic, and 90 normal skin biopsies, and applied computational approaches to identify and characterize expressed lncRNAs. We detect 2,942 previously annotated and 1,080 novel lncRNAs which are expected to be skin specific. Notably, over 40% of the novel lncRNAs are differentially expressed and the proportions of differentially expressed transcripts among protein-coding mRNAs and previously-annotated lncRNAs are lower in psoriasis lesions versus uninvolved or normal skin. We find that many lncRNAs, in particular those that are differentially expressed, are co-expressed with genes involved in immune related functions, and that novel lncRNAs are enriched for localization in the epidermal differentiation complex. We also identify distinct tissue-specific expression patterns and epigenetic profiles for novel lncRNAs, some of which are shown to be regulated by cytokine treatment in cultured human keratinocytes.

CONCLUSIONS

Together, our results implicate many lncRNAs in the immunopathogenesis of psoriasis, and our results provide a resource for lncRNA studies in other autoimmune diseases.

Psoriasis: a mixed autoimmune and autoinflammatory disease

In recent years marked progress has been made in our understanding of the critical biologic and immunologic pathways involved in psoriasis. Genetic studies have demonstrated that susceptibility to psoriasis involves components of both the adaptive and innate immune system and not surprisingly activation of both of these arms of the immune system is found in psoriatic skin. While adaptive immune responses predominate in chronic plaque psoriasis, innate and autoinflammatory responses dominate in pustular forms of psoriasis, with other clinical subtypes extending on a spectrum between plaque and pustular psoriasis. This makes psoriasis a unique disease where both autoimmune and autoinflammatory responses co-exist, with the balance between the two being critical in shaping its clinical presentation.

Menstrual Hygiene: How Hygienic is the Adolescent Girl?

Background:

Menstruation and menstrual practices are still clouded by taboos and socio-cultural restrictions resulting in adolescent girls remaining ignorant of the scientific facts and hygienic health practices, which sometimes result into adverse health outcomes.

Objectives:

(i) To elicit the beliefs, conception and source of information regarding menstruation among the study population and (ii) to find out the status of menstrual hygiene among adolescent girls.

Materials and Methods:

A descriptive, cross-sectional study was conducted among 160 adolescent girls of a secondary school situated in the field practice area of Rural Health Unit and Training Center, Singur, West Bengal, with the help of a pre-designed and pre-tested questionnaire. Data were analyzed statistically by simple proportions.

Results:

Out of 160 respondents, 108 (67.5%) girls were aware about menstruation prior to attainment of menarche. Mother was the first informant regarding menstruation in case of 60 (37.5%) girls. One hundred and thirty-eight (86.25%) girls believed it as a physiological process. Seventy-eight (48.75%) girls knew the use of sanitary pad during menstruation. Regarding practices, only 18 (11.25%) girls used sanitary pads during menstruation. For cleaning purpose, 156 (97.5%) girls used both soap and water. Regarding restrictions practiced, 136 (85%) girls practised different restrictions during menstruation.

Conclusions:

Menstrual hygiene, a very important risk factor for reproductive tract infections, is a vital aspect of health education for adolescent girls. Educational television programmes, trained school nurses/health personnel, motivated school teachers and knowledgeable parents can play a very important role in transmitting the vital message of correct menstrual hygiene to the adolescent girl of today.

Imiquimod has strain-dependent effects in mice and does not uniquely model human psoriasis

BACKGROUND

Imiquimod (IMQ) produces a cutaneous phenotype in mice frequently studied as an acute model of human psoriasis. Whether this phenotype depends on strain or sex has never been systematically investigated on a large scale. Such effects, however, could lead to conflicts among studies, while further impacting study outcomes and efforts to translate research findings.

METHODS

RNA-seq was used to evaluate the psoriasiform phenotype elicited by 6 days of Aldara (5% IMQ) treatment in both sexes of seven mouse strains (C57BL/6 J (B6), BALB/cJ, CD1, DBA/1 J, FVB/NJ, 129X1/SvJ, and MOLF/EiJ).

RESULTS

In most strains, IMQ altered gene expression in a manner consistent with human psoriasis, partly due to innate immune activation and decreased homeostatic gene expression. The response of MOLF males was aberrant, however, with decreased expression of differentiation-associated genes (elevated in other strains). Key aspects of the IMQ response differed between the two most commonly studied strains (BALB/c and B6). Compared with BALB/c, the B6 phenotype showed increased expression of genes associated with DNA replication, IL-17A stimulation, and activated CD8+ T cells, but decreased expression of genes associated with interferon signaling and CD4+ T cells. Although IMQ-induced expression shifts mirrored psoriasis, responses in BALB/c, 129/SvJ, DBA, and MOLF mice were more consistent with other human skin conditions (e.g., wounds or infections). IMQ responses in B6 mice were most consistent with human psoriasis and best replicated expression patterns specific to psoriasis lesions.

CONCLUSIONS

These findings demonstrate strain-dependent aspects of IMQ dermatitis in mice. We have shown that IMQ does not uniquely model psoriasis but in fact triggers a core set of pathways active in diverse skin diseases. Nonetheless, our findings suggest that B6 mice provide a better background than other strains for modeling psoriasis disease mechanisms.

Pregnancy outcome following gestational exposure to venlafaxine: a multicenter prospective controlled study

OBJECTIVE

Because there are no studies available on the safety of venlafaxine during pregnancy, the authors' goal in this study was to determine whether venlafaxine increases the risk for major malformations.

METHOD

Data on 150 women exposed to venlafaxine during pregnancy in seven pregnancy counseling centers were compared with data from studies of pregnant women who 1) received selective serotonin reuptake inhibitor antidepressants (SSRIs) (N=150) and 2) who received nonteratogenic drugs (N=150).

RESULTS

Among the 150 women who were exposed to venlafaxine during pregnancy, 125 had live births, 18 had spontaneous abortions, and seven had therapeutic abortions; two of the babies had major malformations. There were no significant differences between these women and the two comparison groups on any of the measures analyzed.

CONCLUSIONS

These results suggest that the use of venlafaxine during pregnancy does not increase the rates of major malformations above the baseline rate of 1%-3%.

Studies on the Interaction of Surfactants with Cationic Dye by Absorption Spectroscopy

The interaction of methyl violet, a cationic dye, with various surfactants, viz. anionic (SDS), nonionic (Triton X-100), and cationic (CTAB), has been investigated spectrophotometrically in submicellar and micellar concentration range. While in the submicellar concentration region of SDS the higher aggregates of the dye are found, in the micellar concentration region the monomer of the dye predominates. With nonionic surfactant the dye is solubilized primarily as the monomer. CTAB produces no perturbation to the visible spectra of the dye. In the presence of strong electrolytes such as NaNO(3) and NaCl the dye aggregates are formed at a much lower SDS concentrations. Copyright 2000 Academic Press.

IFN-γ enhances cell-mediated cytotoxicity against keratinocytes via JAK2/STAT1 in lichen planus

Lichen planus (LP) is a chronic debilitating inflammatory disease of unknown etiology affecting the skin, nails, and mucosa with no current FDA-approved treatments. It is histologically characterized by dense infiltration of T cells and epidermal keratinocyte apoptosis. Using global transcriptomic profiling of patient skin samples, we demonstrate that LP is characterized by a type II interferon (IFN) inflammatory response. The type II IFN, IFN-γ, is demonstrated to prime keratinocytes and increase their susceptibility to CD8⁺ T cell-mediated cytotoxic responses through MHC class I induction in a coculture model. We show that this process is dependent on Janus kinase 2 (JAK2) and signal transducer and activator of transcription 1 (STAT1), but not JAK1 or STAT2 signaling. Last, using drug prediction algorithms, we identify JAK inhibitors as promising therapeutic agents in LP and demonstrate that the JAK1/2 inhibitor baricitinib fully protects keratinocytes against cell-mediated cytotoxic responses in vitro. In summary, this work elucidates the role and mechanisms of IFN-γ in LP pathogenesis and provides evidence for the therapeutic use of JAK inhibitors to limit cell-mediated cytotoxicity in patients with LP.

Single cell and spatial sequencing define processes by which keratinocytes and fibroblasts amplify inflammatory responses in psoriasis

The immunopathogenesis of psoriasis, a common chronic inflammatory disease of the skin, is incompletely understood. Here we demonstrate, using a combination of single cell and spatial RNA sequencing, IL-36 dependent amplification of IL-17A and TNF inflammatory responses in the absence of neutrophil proteases, which primarily occur within the supraspinous layer of the psoriatic epidermis. We further show that a subset of SFRP2+ fibroblasts in psoriasis contribute to amplification of the immune network through transition to a pro-inflammatory state. The SFRP2+ fibroblast communication network involves production of CCL13, CCL19 and CXCL12, connected by ligand-receptor interactions to other spatially proximate cell types: CCR2+ myeloid cells, CCR7+ LAMP3+ dendritic cells, and CXCR4 expressed on both CD8+ Tc17 cells and keratinocytes, respectively. The SFRP2+ fibroblasts also express cathepsin S, further amplifying inflammatory responses by activating IL-36G in keratinocytes. These data provide an in-depth view of psoriasis pathogenesis, which expands our understanding of the critical cellular participants to include inflammatory fibroblasts and their cellular interactions.

Molecular cloning and expression of cDNA encoding the enzyme that controls conversion of high-mannose to hybrid and complex N-glycans: UDP-N-acetylglucosamine: alpha-3-D-mannoside beta-1,2-N-acetylglucosaminyltransferase I

UDP-GlcNAc:alpha-3-D-mannoside beta-1,2-N-acetylglucosaminyltransferase I (GnT I; EC 2.4.1.101) catalyzes an essential first step in the conversion of high-mannose N-glycans to hybrid and complex N-glycans. Cloning of the gene encoding this enzyme was carried out by mixed oligonucleotide-primed polymerase chain reaction amplification of rabbit liver single-stranded cDNA using sense and antisense 20- to 24-base-pair (bp) primers. A rabbit liver library in phage lambda gt10 yielded a 2.5-kilobase (kb) cDNA with a 447-amino acid coding sequence. None of the nine asparagine residues were in an Asn-Xaa-(Ser or Thr) sequence, indicating that the protein is not N-glycosylated. There is no sequence homology to other previously cloned glycosyltransferases, but GnT I appears to have a domain structure typical of these enzymes--i.e., a short amino-terminal domain, a transmembrane domain, a "neck" region, and a large carboxyl-terminal catalytic domain. RNA was transcribed off the 2.5-kb cDNA, and in vitro translation with rabbit reticulocyte lysate yielded a 52-kDa protein with GnT I activity.

Neovascularization during venous thrombosis organization: a preliminary study

PURPOSE

Thrombus organization after venous thromboembolism leading to recanalization occurs at a variable rate. The angiogenic chemokine interleukin-8 (IL-8) has been found in thrombus months after thrombus initiation. We hypothesize that thrombus organization involves neovascularization and leukocyte influx and that IL-8 administered at thrombus induction will promote thrombus organization.

METHODS

A group of rats underwent inferior vena caval occlusive thrombosis. At thrombus induction and every 24 hours, the rats were administered IL-8 (1 microgram) or serum albumin. The rats were killed at either day 4, day 8, or day 12, and, at death, colloidal carbon was perfused via the heart. The inferior vena cava was isolated, measured, weighed, and formalin fixed. The sections were stained with anti-polymorphonuclear leukocyte antibody, the endothelial marker factor VIII-related antigen, and with hematoxylin and eosin. Thrombus neovascularization (colloidal carbon) with morphometric analysis was normalized to the total thrombus area. In addition, the rats underwent perfusion with fluorescein isothiocyanate dextran (molecular weight, 150,000) at death to correlate with colloidal carbon perfusion, and thrombus fluorescence was determined.

RESULTS

Thrombus cellularity initially involved neutrophils, followed by monocytes. Significantly more neutrophils, monocytes, and cells that were defined as spindle shaped (fibroblasts and endothelial cells) were noted in the animals treated with IL-8. Neovascularization was significantly increased at day 4 in the animals treated with IL-8 versus the animals treated with serum albumin and was corroborated with a significant increase in thrombus fluorescein isothiocyanate dextran fluorescence at day 4 in the rats treated with IL-8. Colloidal carbon perfusion was noted within vascular channels without extravasation and colocalized with factor VIII-related antigen.

CONCLUSION

This study shows that thrombus organization involves neovascularization and that IL-8 augments thrombus organization.

A gene network regulated by the transcription factor VGLL3 as a promoter of sex-biased autoimmune diseases

Autoimmune diseases affect 7.5% of the US population, and they are among the leading causes of death and disability. A notable feature of many autoimmune diseases is their greater prevalence in females than in males, but the underlying mechanisms of this have remained unclear. Through the use of high-resolution global transcriptome analyses, we demonstrated a female-biased molecular signature associated with susceptibility to autoimmune disease and linked this to extensive sex-dependent co-expression networks. This signature was independent of biological age and sex-hormone regulation and was regulated by the transcription factor VGLL3, which also had a strong female-biased expression. On a genome-wide level, VGLL3-regulated genes had a strong association with multiple autoimmune diseases, including lupus, scleroderma and Sjögren's syndrome, and had a prominent transcriptomic overlap with inflammatory processes in cutaneous lupus. These results identified a VGLL3-regulated network as a previously unknown inflammatory pathway that promotes female-biased autoimmunity. They demonstrate the importance of studying immunological processes in females and males separately and suggest new avenues for therapeutic development.

IFN-γ and TNF-α synergism may provide a link between psoriasis and inflammatory atherogenesis

Chronic inflammation is a critical component of atherogenesis, however, reliable human translational models aimed at characterizing these mechanisms are lacking. Psoriasis, a chronic inflammatory skin disease associated with increased susceptibility to atherosclerosis, provides a clinical human model that can be utilized to investigate the links between chronic inflammation and atherosclerosis development. We sought to investigate key biological processes in psoriasis skin and human vascular tissue to identify biological components that may promote atherosclerosis in chronic inflammatory conditions. Using a bioinformatics approach of human skin and vascular tissue, we determined IFN-γ and TNF-α are the dominant pro-inflammatory signals linking atherosclerosis and psoriasis. We then stimulated primary aortic endothelial cells and ex-vivo atherosclerotic tissue with IFN-γ and TNF-α and found they synergistically increased monocyte and T-cell chemoattractants, expression of adhesion molecules on the endothelial cell surface, and decreased endothelial barrier integrity in vitro, therefore increasing permeability. Our data provide strong evidence of synergism between IFN-γ and TNF- α in inflammatory atherogenesis and provide rationale for dual cytokine antagonism in future studies.

RNA-Seq Analysis of IL-1B and IL-36 Responses in Epidermal Keratinocytes Identifies a Shared MyD88-Dependent Gene Signature

IL-36 cytokines have recently emerged as mediators of inflammation in autoimmune conditions including psoriasis vulgaris (PsV) and generalized pustular psoriasis (GPP). This study used RNA-seq to profile the transcriptome of primary epidermal keratinocytes (KCs) treated with IL-1B, IL-36A, IL-36B, or IL-36G. We identified some early IL-1B-specific responses (8 h posttreatment), but nearly all late IL-1B responses were replicated by IL-36 cytokines (24 h posttreatment). Type I and II interferon genes exhibited time-dependent response patterns, with early induction (8 h) followed by no response or repression (24 h). Altogether, we identified 225 differentially expressed genes (DEGs) with shared responses to all 4 cytokines at both time points (8 and 24 h). These involved upregulation of ligands (IL1A, IL1B, and IL36G) and activating proteases (CTSS) but also upregulation of inhibitors such as IL1RN and IL36RN. Shared IL-1B/IL-36 DEGs overlapped significantly with genes altered in PsV and GPP skin lesions, as well as genes near GWAS loci linked to autoimmune and autoinflammatory diseases (e.g., PsV, psoriatic arthritis, inflammatory bowel disease, and primary biliary cholangitis). Inactivation of MyD88 adapter protein using CRISPR/Cas9 completely abolished expression responses of such DEGs to IL-1B and IL-36G stimulation. These results provide a global view of IL-1B and IL-36 expression responses in epidermal KCs with fine-scale characterization of time-dependent and cytokine-specific response patterns. Our findings support an important role for IL-1B and IL-36 in autoimmune or autoinflammatory conditions and show that MyD88 adaptor protein mediates shared IL-1B/IL-36 responses.

Isolation, characterization and inactivation of the mouse Mgat3 gene: the bisecting N-acetylglucosamine in asparagine-linked oligosaccharides appears dispensable for viability and reproduction

The biosynthesis of complex asparagine (N)-linked oligosaccharides in vertebrates proceeds with the linkage of N-acetylglucosamine (GlcNAc) to the core mannose residues. UDP-N-acetylglucosamine:beta-D-mannoside beta 1-4 N-acetylglucosaminyltransferase III (GlcNAc-TIII, EC2.4.1.144) catalyzes the addition of GlcNAc to the mannose that is itself beta 1-4 linked to underlying N-acetylglucosamine. GlcNAc-TIII thereby produces what is known as a 'bisecting' GlcNAc linkage which is found on various hybrid and complex N-glycans. GlcNAc-TIII can also play a regulatory role in N-glycan biosynthesis as addition of the bisecting GlcNAc eliminates the potential for alpha-mannosidase-II, GlcNAc-TII, GlcNAc-TIV, GlcNAc-TV, and core alpha 1-6-fucosyltransferase to act subsequently. To investigate the physiologic relevance of GlcNAc-TIII function and bisected N-glycans, the mouse gene encoding GlcNAc-TIII (Mgat3) was cloned, characterized, and inactivated using Cre/loxP site-directed recombination. The Mgat3 gene is highly conserved in comparison to the rat and human homologs and is normally expressed at high levels in mammalian brain and kidney tissues. Using fluorescence in situ hybridization (FISH), the Mgat3 gene was regionally mapped to chromosome 15E11, near the Scn8a sodium channel gene at 15F1. Following homologous recombination in embryonic stem cells and Cre mediated gene deletion, Mgat3-deficient mice were produced that lacked GlcNAc-TIII activity and were deficient in E4-PHA visualized GlcNAc-bisected N-linked oligosaccharides. Nevertheless, GlcNAc-TIII deficient mice were found to be viable and reproduced normally. Moreover, such mice exhibited normal cellularity and morphology among organs including brain and kidney. No alterations were apparent in circulating leukocytes, erythrocytes or in serum metabolite levels that reflect kidney function. We thus find that GlcNAc-TIII and the bisecting GlcNAc in N-glycans appear dispensable for normal development, homeostasis and reproduction in the mouse.

Lupus Skin Is Primed for IL-6 Inflammatory Responses through a Keratinocyte-Mediated Autocrine Type I Interferon Loop

Cutaneous lupus erythematosus is a disfiguring and common manifestation in systemic lupus erythematosus, and the etiology of this predisposition for cutaneous inflammation is unknown. Here, we sought to examine the keratinocyte as an important source of IL-6 and define the mechanism for its increased production in cutaneous lupus erythematosus. Evaluation of discoid and subacute cutaneous lupus erythematosus lesions showed significant epidermal up-regulation of IL-6 compared with control via real-time PCR and immunohistochemistry. Keratinocytes from unaffected skin of lupus patients produced significantly more IL-6 compared with healthy control subjects after exposure to toll-like receptor 2, 3, or 4 agonists or exposure to UVB radiation. Pretreatment with type I interferons (IFN-α and IFN-κ) increased IL-6 production by control keratinocytes, and type I IFN blockade decreased IL-6 secretion by lupus keratinocytes. Secretion of keratinocyte-specific IFN-κ was significantly increased after toll-like receptor 2 and UVB treatment in lupus keratinocytes, and neutralization of IFN-κ decreased IL-6 production by lupus keratinocytes. Thus, lupus keratinocytes are primed for IL-6 hyperproduction in a type I IFN-dependent manner. Increased production of IFN-κ by lupus keratinocytes drives this response, indicating that IFN-κ may play a pathogenic role in cutaneous lupus erythematosus and serve as a target for treatment.

Proteogenomic analysis of psoriasis reveals discordant and concordant changes in mRNA and protein abundance

BACKGROUND

Psoriasis is a chronic disease characterized by the development of scaly red skin lesions and possible co-morbid conditions. The psoriasis lesional skin transcriptome has been extensively investigated, but mRNA levels do not necessarily reflect protein abundance. The purpose of this study was therefore to compare differential expression patterns of mRNA and protein in psoriasis lesions.

METHODS

Lesional (PP) and uninvolved (PN) skin samples from 14 patients were analyzed using high-throughput complementary DNA sequencing (RNA-seq) and liquid chromatography-tandem mass spectrometry (LC-MS/MS).

RESULTS

We identified 4122 differentially expressed genes (DEGs) along with 748 differentially expressed proteins (DEPs). Global shifts in mRNA were modestly correlated with changes in protein abundance (r = 0.40). We identified similar numbers of increased and decreased DEGs, but 4-fold more increased than decreased DEPs. Ribosomal subunit and translation proteins were elevated within lesions, without a corresponding shift in mRNA expression (RPL3, RPS8, RPL11). We identified 209 differentially expressed genes/proteins (DEGPs) with corresponding trends at the transcriptome and proteome levels. Most DEGPs were similarly altered in at least one other skin disease. Psoriasis-specific and non-specific DEGPs had distinct cytokine-response patterns, with only the former showing disproportionate induction by IL-17A in cultured keratinocytes.

CONCLUSIONS

Our findings reveal global imbalance between the number of increased and decreased proteins in psoriasis lesions, consistent with heightened translation. This effect could not have been discerned from mRNA profiling data alone. High-confidence DEGPs were identified through transcriptome-proteome integration. By distinguishing between psoriasis-specific and non-specific DEGPs, our analysis uncovered new functional insights that would otherwise have been overlooked.

Interleukin-8 administration enhances venous thrombosis resolution in a rat model

BACKGROUND

Therapy for deep vein thrombosis (DVT) resolution in those patients in whom a complication or contraindication to anticoagulation occurs is limited. As prior work suggests that thrombus maturation involves early influx of neutrophils (PMN) and neovascularization, we hypothesized that administering the proinflammatory/proangiogenic chemokine interleukin (IL)-8 might accelerate thrombus resolution.

MATERIALS AND METHODS

An established rodent model of DVT (inferior vena cava [IVC] ligation) was used whereby daily intravenous recombinant human IL-8 (1 microg) or vehicle control was administered, with sacrifice at 4 and 8 days. Prior to sacrifice and at harvest, duplex ultrasound of the DVT and femoral venous pressure measurements were performed. Thrombi were analyzed by immunohistochemical techniques for PMN, monocytes, and neovascularization; for chemokines, by enzyme-linked immunoassay; and fibrosis, by hydroxyproline assay and trichrome staining.

RESULTS

IL-8 accelerated thrombus dissolution 4 days after IVC ligation, with 6-fold increased thrombus blood flow by duplex ultrasound and a 23% increased absolute femoral venous pressure compared with controls (both P < 0.05). These findings may be partially explained by the fact that animals receiving IL-8, as compared with controls, had 2.5-fold greater thrombus neovascularization (with a trend continuing to 8 days) and increased PMN at 4 days. Thrombus vascular endothelial growth factor was significantly reduced at 8 days postligation, while monocyte chemotactic protein-1 and macrophage inflammatory protein-1alpha were not altered by IL-8 administration. At 8 days post-IVC-ligation, fibrosis was 12-fold greater with IL-8 treatment compared with controls.

CONCLUSIONS

A proinflammatory/proangiogenic thrombus milieu, as conferred by IL-8, enhances thrombus resolution and underscores the important relationship between neovascularity and inflammation.

The human UDP-N-acetylglucosamine: alpha-6-D-mannoside-beta-1,2- N-acetylglucosaminyltransferase II gene (MGAT2). Cloning of genomic DNA, localization to chromosome 14q21, expression in insect cells and purification of the recombinant protein

UDP-GlcNAc:alpha-6-D-mannoside [GlcNAc to Man alpha 1-6] beta-1,2-N-acetylglucosaminyltransferase II (GlcNAc-T II, EC 2.4.1.143) is a Golgi enzyme catalyzing an essential step in the conversion of oligomannose to complex N-glycans. A 1.2-kb probe from a rat liver cDNA encoding GlcNAc-T II was used to screen a human genomic DNA library in lambda EMBL3. Southern analysis of restriction endonuclease digests of positive phage clones identified two hybridizing fragments (3.0 and 3.5 kb) which were subcloned into pBlueScript. The inserts of the resulting plasmids (pHG30 and pHG36) are over-lapping clones containing 5.5 kb of genomic DNA. The pHG30 insert (3.0 kb) contains a 1341-bp open reading frame encoding a 447-amino-acid protein, 250 bp of G + C-rich 5'-upstream sequence and 1.4 kb of 3'-downstream sequence. The pHG36 insert (3.5 kb) contains 2.75 kb of 5'-upstream sequence and 750 bp of the 5'-end of the open reading frame. The protein sequence showed the domain structure typical of all previously cloned glycosyltransferases, i.e. a short 9-residue putative cytoplasmic N-terminal domain, a 20-residue hydrophobic non-cleavable putative signal-anchor domain and a 418-residue C-terminal catalytic domain. Northern analysis of human tissues showed a major message at 3 kb and minor signals at 2 and 4.5 kb. There is no sequence similarity to any previously cloned glycosyltransferases including human UDP-GlcNAc:alpha-3-D-mannoside [GlcNAc to Man alpha 1-3] beta-1,2-N-acetylglucosaminyltransferase I (GlcNAc-T I) which has 445 amino acids with a 418-residue C-terminal catalytic domain. The human GlcNAc-T I and II genes (MGAT1 and MGAT2) map to chromosome bands 5q35 and 14q21, respectively, by fluorescence in situ hybridization. The entire coding regions of human GlcNAc-T I and II are each on a single exon. There is 92% identity between the amino acid sequences of the catalytic domains of human and rat GlcNAc-T II. Southern analysis of restriction enzyme digests of human genomic DNA indicates that there is only a single copy of the MGAT2 gene. The full-length coding region of GlcNAc-T II has been expressed in the baculovirus/Sf9 insect cell system, the recombinant enzyme has been purified to near homogeneity with a specific activity of about 20 mumol.min-1.mg-1 and the product synthesized by the recombinant enzyme has been identified by high-resolution 1H-NMR spectroscopy and mass spectrometry.