Cell-free circulating ALU repeats in serum have a prognostic value for colorectal cancer patients

BACKGROUND

Carcinoembryonic antigen (CEA) is the only established serum biomarker for colorectal cancer (CRC). To facilitate therapy decisions and improve the overall survival of CRC patients, prognostic biomarkers are required.

OBJECTIVE

We studied the prognostic value of five different cell free circulating DNA (fcDNA) fragments. The potential markers were ALU115, ALU247, LINE1-79, LINE1-300 and ND1-mt.

METHODS

The copy numbers of the DNA fragments were measured in the peripheral blood serum of 268 CRC patients using qPCR, the results were compared to common and previously described markers.

RESULTS

We found that ALU115 and ALU247 fcDNA levels correlate significantly with several clinicopathological parameters. An increased amount of ALU115 and ALU247 fcDNA fragments coincides with methylation of HPP1 (P< 0.001; P< 0.01), which proved to be a prognostic marker itself in former studies and also with increased CEA level (P< 0.001). ALU115 and ALU247 can define patients with poor survival in UICC stage IV (Alu115: HR = 2.9; 95% Cl 1.8-4.8, P< 0.001; Alu247: HR = 2.2; 95% Cl 1.3-3.6; P= 0.001). Combining ALU115 and HPP1, the prognostic value in UICC stage IV is highly significant (P< 0.001).

CONCLUSIONS

This study shows that an increased level of ALU fcDNA is an independent prognostic biomarker for advanced colorectal cancer disease.

Lung emphysema and impaired macrophage elastase clearance in mucolipin 3 deficient mice

Lung emphysema and chronic bronchitis are the two most common causes of chronic obstructive pulmonary disease. Excess macrophage elastase MMP-12, which is predominantly secreted from alveolar macrophages, is known to mediate the development of lung injury and emphysema. Here, we discovered the endolysosomal cation channel mucolipin 3 (TRPML3) as a regulator of MMP-12 reuptake from broncho-alveolar fluid, driving in two independently generated Trpml3-/- mouse models enlarged lung injury, which is further exacerbated after elastase or tobacco smoke treatment. Mechanistically, using a Trpml3IRES-Cre/eR26-τGFP reporter mouse model, transcriptomics, and endolysosomal patch-clamp experiments, we show that in the lung TRPML3 is almost exclusively expressed in alveolar macrophages, where its loss leads to defects in early endosomal trafficking and endocytosis of MMP-12. Our findings suggest that TRPML3 represents a key regulator of MMP-12 clearance by alveolar macrophages and may serve as therapeutic target for emphysema and chronic obstructive pulmonary disease.

Uncovering the molecular identity of cardiosphere-derived cells (CDCs) by single-cell RNA sequencing

Cardiosphere-derived cells (CDCs) generated from human cardiac biopsies have been shown to have disease-modifying bioactivity in clinical trials. Paradoxically, CDCs' cellular origin in the heart remains elusive. We studied the molecular identity of CDCs using single-cell RNA sequencing (sc-RNAseq) in comparison to cardiac non-myocyte and non-hematopoietic cells (cardiac fibroblasts/CFs, smooth muscle cells/SMCs and endothelial cells/ECs). We identified CDCs as a distinct and mitochondria-rich cell type that shared biological similarities with non-myocyte cells but not with cardiac progenitor cells derived from human-induced pluripotent stem cells. CXCL6 emerged as a new specific marker for CDCs. By analysis of sc-RNAseq data from human right atrial biopsies in comparison with CDCs we uncovered transcriptomic similarities between CDCs and CFs. By direct comparison of infant and adult CDC sc-RNAseq data, infant CDCs revealed GO-terms associated with cardiac development. To analyze the beneficial effects of CDCs (pro-angiogenic, anti-fibrotic, anti-apoptotic), we performed functional in vitro assays with CDC-derived extracellular vesicles (EVs). CDC EVs augmented in vitro angiogenesis and did not stimulate scarring. They also reduced the expression of pro-apoptotic Bax in NRCMs. In conclusion, CDCs were disclosed as mitochondria-rich cells with unique properties but also with similarities to right atrial CFs. CDCs displayed highly proliferative, secretory and immunomodulatory properties, characteristics that can also be found in activated or inflammatory cell types. By special culture conditions, CDCs earn some bioactivities, including angiogenic potential, which might modify disease in certain disorders.

Sequential Defects in Cardiac Lineage Commitment and Maturation Cause Hypoplastic Left Heart Syndrome

BACKGROUND

Complex molecular programs in specific cell lineages govern human heart development. Hypoplastic left heart syndrome (HLHS) is the most common and severe manifestation within the spectrum of left ventricular outflow tract obstruction defects occurring in association with ventricular hypoplasia. The pathogenesis of HLHS is unknown, but hemodynamic disturbances are assumed to play a prominent role.

METHODS

To identify perturbations in gene programs controlling ventricular muscle lineage development in HLHS, we performed whole-exome sequencing of 87 HLHS parent-offspring trios, nuclear transcriptomics of cardiomyocytes from ventricles of 4 patients with HLHS and 15 controls at different stages of heart development, single cell RNA sequencing, and 3D modeling in induced pluripotent stem cells from 3 patients with HLHS and 3 controls.

RESULTS

Gene set enrichment and protein network analyses of damaging de novo mutations and dysregulated genes from ventricles of patients with HLHS suggested alterations in specific gene programs and cellular processes critical during fetal ventricular cardiogenesis, including cell cycle and cardiomyocyte maturation. Single-cell and 3D modeling with induced pluripotent stem cells demonstrated intrinsic defects in the cell cycle/unfolded protein response/autophagy hub resulting in disrupted differentiation of early cardiac progenitor lineages leading to defective cardiomyocyte subtype differentiation/maturation in HLHS. Premature cell cycle exit of ventricular cardiomyocytes from patients with HLHS prevented normal tissue responses to developmental signals for growth, leading to multinucleation/polyploidy, accumulation of DNA damage, and exacerbated apoptosis, all potential drivers of left ventricular hypoplasia in absence of hemodynamic cues.

CONCLUSIONS

Our results highlight that despite genetic heterogeneity in HLHS, many mutations converge on sequential cellular processes primarily driving cardiac myogenesis, suggesting novel therapeutic approaches.

Parallel Murine and Human Aortic Wall Genomics Reveals Metabolic Reprogramming as Key Driver of Abdominal Aortic Aneurysm Progression

Background While numerous interventions effectively interfered with abdominal aortic aneurysm (AAA) formation/progression in preclinical models, none of the successes translated into clinical success. Hence, a systematic exploration of parallel and divergent processes in clinical AAA disease and its 2 primary models (the porcine pancreatic elastase and angiotensin-II infusion [AngII] murine model) was performed to identify mechanisms relevant for aneurysm disease. Methods and Results This study combines Movat staining and pathway analysis for histological and genomic comparisons between clinical disease and its models. The impact of a notable genomic signal for metabolic reprogramming was tested in a rescue trial (AngII model) evaluating the impact of 1-(4-pyridinyl)-3-(2-quinolinyl)-2-propen-1-one (PFK15)-mediated interference with main glycolytic switch PFKFB3. Histological evaluation characterized the AngII model as a dissection model that is accompanied by adventitial fibrosis. The porcine pancreatic elastase model showed a transient inflammatory response and aortic dilatation, followed by stabilization and fibrosis. Normalization of the genomic responses at day 14 confirmed the self-limiting nature of the porcine pancreatic elastase model. Clear parallel genomic responses with activated adaptive immune responses, and particularly strong signals for metabolic switching were observed in human AAA and the AngII model. Rescue intervention with the glycolysis inhibitor PFK15 in the AngII model showed that interference with the glycolytic switching quenches aneurysm formation. Conclusions Despite clear morphological contrasts, remarkable genomic parallels exist for clinical AAA disease and the AngII model. The metabolic response appears causatively involved in AAA progression and provides a novel therapeutic target. The clear transient genomic response classifies the porcine pancreatic elastase model as a disease initiation model.

High-resolution serum proteome trajectories in COVID-19 reveal patient-specific seroconversion

A deeper understanding of COVID-19 on human molecular pathophysiology is urgently needed as a foundation for the discovery of new biomarkers and therapeutic targets. Here we applied mass spectrometry (MS)-based proteomics to measure serum proteomes of COVID-19 patients and symptomatic, but PCR-negative controls, in a time-resolved manner. In 262 controls and 458 longitudinal samples of 31 patients, hospitalized for COVID-19, a remarkable 26% of proteins changed significantly. Bioinformatics analyses revealed co-regulated groups and shared biological functions. Proteins of the innate immune system such as CRP, SAA1, CD14, LBP, and LGALS3BP decreased early in the time course. Regulators of coagulation (APOH, FN1, HRG, KNG1, PLG) and lipid homeostasis (APOA1, APOC1, APOC2, APOC3, PON1) increased over the course of the disease. A global correlation map provides a system-wide functional association between proteins, biological processes, and clinical chemistry parameters. Importantly, five SARS-CoV-2 immunoassays against antibodies revealed excellent correlations with an extensive range of immunoglobulin regions, which were quantified by MS-based proteomics. The high-resolution profile of all immunoglobulin regions showed individual-specific differences and commonalities of potential pathophysiological relevance.

SARS-CoV-2 antibody immunoassays in serial samples reveal earlier seroconversion in acutely ill COVID-19 patients developing ARDS

OBJECTIVES

During the COVID-19 pandemic, SARS-CoV-2 antibody testing has been suggested for (1) screening populations for disease prevalence, (2) diagnostics, and (3) guiding therapeutic applications. Here, we conducted a detailed clinical evaluation of four Anti-SARS-CoV-2 immunoassays in samples from acutely ill COVID-19 patients and in two negative cohorts.

METHODS

443 serum specimens from serial sampling of 29 COVID-19 patients were used to determine clinical sensitivities. Patients were stratified for the presence of acute respiratory distress syndrome (ARDS). Individual serum specimens from a pre-COVID-19 cohort of 238 healthy subjects and from a PCR-negative clinical cohort of 257 patients were used to determine clinical specificities. All samples were measured side-by-side with the Anti-SARS-CoV-2-ELISA (IgG), Anti-SARS-CoV-2-ELISA (IgA) and Anti-SARS-CoV-2-NCP-ELISA (IgG) (Euroimmun AG, Lübeck, Germany) and the Elecsys Anti-SARS-CoV-2 ECLIA (Roche Diagnostics International, Rotkreuz, Switzerland).

RESULTS

Median seroconversion occurred earlier in ARDS patients (8-9 days) than in non-ARDS patients (11-17 days), except for EUR N-IgG. Rates of positivity and mean signal ratios in the ARDS group were significantly higher than in the non-ARDS group. Sensitivities between the four tested immunoassays were equivalent. In the set of negative samples, the specificity of the Anti-SARS-CoV-2-ELISA (IgA) was lower (93.9%) compared to all other assays (≥98.8%) and the specificity of Anti-SARS-CoV-2-NCP-ELISA (IgG) was lower (98.8%) than that of Elecsys Anti-SARS-CoV-2 (100%).

CONCLUSIONS

Serial sampling in COVID-19 patients revealed earlier seroconversion and higher signal ratios of SARS-CoV-2 antibodies as a potential risk marker for the development of ARDS, suggesting a utility for antibody testing in acutely diseased patients.

Head-to-head study of oxelumab and adalimumab in a mouse model of ulcerative colitis based on NOD/Scid IL2Rγnull mice reconstituted with human peripheral blood mononuclear cells

This study's aim was to demonstrate that the combination of patient immune profiling and testing in a humanized mouse model of ulcerative colitis (UC) might lead to patient stratification for treatment with oxelumab. First, immunological profiles of UC patients and non-UC donors were analyzed for CD4⁺ T cells expressing OX40 (CD134; also known as TNFRSF4) and CD14⁺ monocytes expressing OX40L (CD252; also known as TNFSF4) by flow cytometric analysis. A significant difference was observed between the groups for CD14⁺ OX40L⁺ (UC: n=11, 85.44±21.17, mean±s.d.; non-UC: n=5, 30.7±34.92; P=0.02), whereas no significant difference was detected for CD4⁺ OX40⁺. CD14⁺ OX40L⁺ monocytes were correlated significantly with T helper 1 and 2 cells. Second, NOD/Scid IL2Rγ null mice were reconstituted with peripheral blood mononuclear cells from UC donors exhibiting elevated levels of OX40L, and the efficacy of oxelumab was compared with that of adalimumab. The clinical, colon and histological scores and the serum concentrations of IL-6, IL-1β and glutamic acid were assessed. Treatment with oxelumab or adalimumab resulted in significantly reduced clinical, colon and histological scores, reduced serum concentrations of IL-6 and reduced frequencies of splenic human effector memory T cells and switched B cells. Comparison of the efficacy of adalimumab and oxelumab by orthogonal partial least squares discrimination analysis revealed that oxelumab was slightly superior to adalimumab; however, elevated serum concentrations of glutamic acid suggested ongoing inflammation. These results suggest that oxelumab addresses the pro-inflammatory arm of inflammation while promoting the remodeling arm and that patients exhibiting elevated levels of OX40L might benefit from treatment with oxelumab.

Summary: The combination of patient profiling and testing in a NOD/Scid IL2Rγ^null mouse model of ulcerative colitis (UC) validates oxelumab as a potential therapeutic in UC.

Circulating Metabolites Differentiate Acute Ischemic Stroke from Stroke Mimics

OBJECTIVE

Early discrimination of patients with ischemic stroke (IS) from stroke mimics (SMs) poses a diagnostic challenge. The circulating metabolome might reflect pathophysiological events related to acute IS. Here, we investigated the utility of early metabolic changes for differentiating IS from SM.

METHODS

We performed untargeted metabolomics on serum samples obtained from patients with IS (N = 508) and SM (N = 349; defined by absence of a diffusion weighted imaging [DWI] positive lesion on magnetic resonance imaging [MRI]) who presented to the hospital within 24 hours after symptom onset (median time from symptom onset to blood sampling = 3.3 hours; interquartile range [IQR] = 1.6-6.7 hours) and from neurologically normal controls (NCs; N = 112). We compared diagnostic groups in a discovery-validation approach by applying multivariable linear regression models, machine learning techniques, and propensity score matching. We further performed a targeted look-up of published metabolite sets.

RESULTS

Levels of 41 metabolites were significantly associated with IS compared to NCs. The top metabolites showing the highest value in separating IS from SMs were asymmetrical and symmetrical dimethylarginine, pregnenolone sulfate, and adenosine. Together, these 4 metabolites differentiated patients with IS from SMs with an area under the curve (AUC) of 0.90 in the replication sample, which was superior to multimodal cranial computed tomography (CT; AUC = 0.80) obtained for routine diagnostics. They were further superior to previously published metabolite sets detected in our samples. All 4 metabolites returned to control levels by day 90.

INTERPRETATION

A set of 4 metabolites with known biological effects relevant to stroke pathophysiology shows unprecedented utility to identify patients with IS upon hospital arrival, thus encouraging further investigation, including multicenter studies. ANN NEUROL 2020;88:736-746.

A modified low-protein infant formula supports adequate growth in healthy, term infants: a randomized, double-blind, equivalence trial

BACKGROUND

A high protein intake in early life is associated with a risk of obesity later in life. The essential amino acid requirements of formula-fed infants have been reassessed recently, enabling a reduction in total protein content and thus in protein intake.

OBJECTIVES

We aimed to assess the safety of an infant formula with a modified amino acid profile and a modified low-protein (mLP) content in healthy term-born infants. Outcomes were compared with a specifically designed control (CTRL) infant formula.

METHODS

In this double-blind, randomized controlled equivalence trial, infants received either mLP (1.7 g protein/100 kcal; n = 90) or CTRL formula (2.1 g protein/100 kcal; n = 88) from enrollment (age ≤ 45 d) to 6 mo of age. A breastfed group served as a reference (n = 67). Anthropometry and body composition were determined at baseline, 17 wk (including safety blood parameters), and 6 mo of age. The primary outcome was daily weight gain from enrollment up until the age of 17 wk (at an equivalence margin of ±3.0 g/d).

RESULTS

Weight gain from baseline (mean ± SD age: 31 ± 9 d) up to the age of 17 wk was equivalent between the mLP and CTRL formula groups (27.9 and 28.8 g/d, respectively; difference: -0.86 g/d; 90% CI: -2.36, 0.63 g/d). No differences in other growth parameters, body composition, or in adverse events were observed. Urea was significantly lower in the mLP formula group than in the CTRL formula group (-0.74 mmol/L; 95% CI: -0.97, -0.51 mmol/L; P < 0.001). Growth rates, fat mass, fat-free mass, and several essential amino acids were significantly higher in both formula groups than in the breastfed reference group.

CONCLUSIONS

Feeding an infant formula with a modified amino acid profile and a lower protein content from an average age of 1 mo until the age of 6 mo is safe and supports an adequate growth, similar to that of infants consuming CTRL formula. This trial was registered at www.trialregister.nl as Trial NL4677.

Short-Chain Fatty Acids Improve Poststroke Recovery via Immunological Mechanisms

Recovery after stroke is a multicellular process encompassing neurons, resident immune cells, and brain-invading cells. Stroke alters the gut microbiome, which in turn has considerable impact on stroke outcome. However, the mechanisms underlying gut-brain interaction and implications for long-term recovery are largely elusive. Here, we tested the hypothesis that short-chain fatty acids (SCFAs), key bioactive microbial metabolites, are the missing link along the gut-brain axis and might be able to modulate recovery after experimental stroke. SCFA supplementation in the drinking water of male mice significantly improved recovery of affected limb motor function. Using in vivo wide-field calcium imaging, we observed that SCFAs induced altered contralesional cortex connectivity. This was associated with SCFA-dependent changes in spine and synapse densities. RNA sequencing of the forebrain cortex indicated a potential involvement of microglial cells in contributing to the structural and functional remodeling. Further analyses confirmed a substantial impact of SCFAs on microglial activation, which depended on the recruitment of T cells to the infarcted brain. Our findings identified that microbiota-derived SCFAs modulate poststroke recovery via effects on systemic and brain resident immune cells.SIGNIFICANCE STATEMENT Previous studies have shown a bidirectional communication along the gut-brain axis after stroke. Stroke alters the gut microbiota composition, and in turn, microbiota dysbiosis has a substantial impact on stroke outcome by modulating the immune response. However, until now, the mediators derived from the gut microbiome affecting the gut-immune-brain axis and the molecular mechanisms involved in this process were unknown. Here, we demonstrate that short-chain fatty acids, fermentation products of the gut microbiome, are potent and proregenerative modulators of poststroke neuronal plasticity at various structural levels. We identified that this effect was mediated via circulating lymphocytes on microglial activation. These results identify short-chain fatty acids as a missing link along the gut-brain axis and as a potential therapeutic to improve recovery after stroke.

Is There an Association or Not?-Investigating the Association of Depressiveness, Physical Activity, Body Composition and Sleep With Mediators of Inflammation

BACKGROUND

Cytokines are mediators of inflammation that contribute to a low-grade inflammation in different disorders like major depression and obesity. It still remains unclear which psychological and medical factors interact with cytokine regulation. In the current investigation, the association between levels of pro-and anti-inflammatory cytokines and anthropometrics, mood state (depressiveness), physical activity and sleep were investigated in a sample of community-dwelled adults.

METHODS

Forty-nine subjects met the inclusion criteria for analyses and were assessed at two time-points (baseline (T1) and follow-up (T2), average T1-T2-interval = 215 days). Serum cytokine measures included the pro-inflammatory cytokines interleukin (IL)-2, IL-12, IFN-γ and TNF-α, the anti-inflammatory cytokines IL-4, IL-5, IL-10 and IL-13 and the granulocyte-macrophage colony-stimulating factor (GM-CSF); anthropometrics were assessed via physical examination, depressiveness was assessed via Beck Depression Inventory (BDI)2, parameters of physical activity (steps, METs) and sleep (night/total sleep duration) were measured via a 1-week actigraphy.

RESULTS

Correlation analyses showed low-to moderate significant relationships between the majority of cytokines and the BDI2 at T1, positive correlation with weight and BMI at T1 and T2, and negative correlations with the number of steps and METs at T2 and T2. Regression analyses for T1 revealed that the BDI2 score was the best positive predictor for the concentrations of all nine cytokines, followed by the number of steps and the nightsleep duration as negative predictors. At T2, the amount of steps was found to be negatively associated with IL-4, IL5, IL-10, GM-CSF, IFN-γ, and TNF-α, whereas the BMI could significantly predict IL-12 and IL-13. The BDI2-score was not significantly associated with any of the cytokines. No associations could be found between dynamics in cytokines from T1 and T2 and changes in any of the variables.

DISCUSSION

The present results indicate an influence of physical activity, subjective well-being and body composition on inflammatory mediators. Since there was no standardized intervention targeting the independent variables between T1 and T2, no assumptions on causality can be drawn from the association results.

Plasma Proteome Profiling to detect and avoid sample-related biases in biomarker studies

Plasma and serum are rich sources of information regarding an individual's health state, and protein tests inform medical decision making. Despite major investments, few new biomarkers have reached the clinic. Mass spectrometry (MS)-based proteomics now allows highly specific and quantitative readout of the plasma proteome. Here, we employ Plasma Proteome Profiling to define quality marker panels to assess plasma samples and the likelihood that suggested biomarkers are instead artifacts related to sample handling and processing. We acquire deep reference proteomes of erythrocytes, platelets, plasma, and whole blood of 20 individuals (> 6,000 proteins), and compare serum and plasma proteomes. Based on spike-in experiments, we determine sample quality-associated proteins, many of which have been reported as biomarker candidates as revealed by a comprehensive literature survey. We provide sample preparation guidelines and an online resource ( www.plasmaproteomeprofiling.org) to assess overall sample-related bias in clinical studies and to prevent costly miss-assignment of biomarker candidates.

Brain-released alarmins and stress response synergize in accelerating atherosclerosis progression after stroke

Stroke induces a multiphasic systemic immune response, but the consequences of this response on atherosclerosis-a major source of recurrent vascular events-have not been thoroughly investigated. We show that stroke exacerbates atheroprogression via alarmin-mediated propagation of vascular inflammation. The prototypic brain-released alarmin high-mobility group box 1 protein induced monocyte and endothelial activation via the receptor for advanced glycation end products (RAGE)-signaling cascade and increased plaque load and vulnerability. Recruitment of activated monocytes via the CC-chemokine ligand 2-CC-chemokine receptor type 2 pathway was critical in stroke-induced vascular inflammation. Neutralization of circulating alarmins or knockdown of RAGE attenuated atheroprogression. Blockage of β3-adrenoreceptors attenuated the egress of myeloid monocytes after stroke, whereas neutralization of circulating alarmins was required to reduce systemic monocyte activation and aortic invasion. Our findings identify a synergistic effect of the sympathetic stress response and alarmin-driven inflammation via RAGE as a critical mechanism of exacerbated atheroprogression after stroke.

Long Noncoding RNAs of the Arterial Wall as Therapeutic Agents and Targets in Atherosclerosis

Long noncoding ribonucleic acids (lncRNAs) have been defined as transcripts which are > 200 ribonucleotides in size and are not translated into protein. Recent work has shown that many lncRNAs do have specific molecular functions and biological effects, and are involved in a growing number of diseases, including atherosclerosis. As a consequence, lncRNAs are also becoming interesting targets for therapeutic intervention. Here, we focus on lncRNAs which are expressed in the arterial wall, and describe potential RNA therapeutic approaches of atherosclerosis by manipulating lncRNAs without affecting genome deoxyribonucleic acid content: Starting out with an overview of all lncRNAs that have so far been implicated in atherosclerosis by in vivo studies, we describe methodologies for their activation, inactivation, and RNA sequence manipulation. We continue by addressing how artificial (nonnative) therapeutic lncRNAs may be designed, and which molecular functions these designer lncRNAs may exploit. We conclude with an outlook on approaches for chemical lncRNA modification, RNA mass production, and site-specific therapeutic delivery.

Association of pyrin mutations and autoinflammation with complex phenotype hidradenitis suppurativa: a case-control study

BACKGROUND

Hidradenitis suppurativa (HS) is a rare, debilitating neutrophilic dermatosis characterized by chronic inflammation of hair follicles. Many inflammatory conditions may accompany HS.

OBJECTIVES

To investigate the association of variants of the MEFV gene with a complex HS phenotype.

METHODS

Firstly, we identified the clinical characteristics of 119 patients with HS with a complex phenotype (Hurley stage III disease and/or additional inflammatory symptoms). Then, we searched for MEFV variants among these patients. The odds ratios (ORs) for pathogenic MEFV mutations were calculated using data from these patients with HS and 191 healthy controls.

RESULTS

The male/female ratio was higher, and the mean age of onset was earlier, in our complex HS group compared with patients with HS in general. Five of the patients with HS (4·2%) had a diagnosis of familial Mediterranean fever (FMF) with a standardized morbidity ratio of 45 [95% confidence interval (CI) 16·50-99·84, P < 0·001] when compared with the frequency of FMF in the general Turkish population. Of the patients with complex HS, 38% were positive for pathogenic variants of MEFV. The OR for carrying a pathogenic MEFV allele was 2·80 (95% CI 1·31-5·97, P < 0·001).

CONCLUSIONS

The frequency of MEFV mutations in the group of patients with complex HS was higher than that in healthy controls, suggesting that MEFV mutations may contribute to the pathogenesis of HS. Understanding the role of autoinflammation in HS is of fundamental importance for the development of novel therapies.

The long noncoding RNA CHROME regulates cholesterol homeostasis in primate

The human genome encodes thousands of long non-coding RNAs (lncRNAs), the majority of which are poorly conserved and uncharacterized. Here we identify a primate-specific lncRNA (CHROME), elevated in the plasma and atherosclerotic plaques of individuals with coronary artery disease, that regulates cellular and systemic cholesterol homeostasis. LncRNA CHROME expression is influenced by dietary and cellular cholesterol via the sterol-activated liver X receptor transcription factors, which control genes mediating responses to cholesterol overload. Using gain- and loss-of-function approaches, we show that CHROME promotes cholesterol efflux and HDL biogenesis by curbing the actions of a set of functionally related microRNAs that repress genes in those pathways. CHROME knockdown in human hepatocytes and macrophages increases levels of miR-27b, miR-33a, miR-33b and miR-128, thereby reducing expression of their overlapping target gene networks and associated biologic functions. In particular, cells lacking CHROME show reduced expression of ABCA1, which regulates cholesterol efflux and nascent HDL particle formation. Collectively, our findings identify CHROME as a central component of the non-coding RNA circuitry controlling cholesterol homeostasis in humans.

GWAS and colocalization analyses implicate carotid intima-media thickness and carotid plaque loci in cardiovascular outcomes

Carotid artery intima media thickness (cIMT) and carotid plaque are measures of subclinical atherosclerosis associated with ischemic stroke and coronary heart disease (CHD). Here, we undertake meta-analyses of genome-wide association studies (GWAS) in 71,128 individuals for cIMT, and 48,434 individuals for carotid plaque traits. We identify eight novel susceptibility loci for cIMT, one independent association at the previously-identified PINX1 locus, and one novel locus for carotid plaque. Colocalization analysis with nearby vascular expression quantitative loci (cis-eQTLs) derived from arterial wall and metabolic tissues obtained from patients with CHD identifies candidate genes at two potentially additional loci, ADAMTS9 and LOXL4. LD score regression reveals significant genetic correlations between cIMT and plaque traits, and both cIMT and plaque with CHD, any stroke subtype and ischemic stroke. Our study provides insights into genes and tissue-specific regulatory mechanisms linking atherosclerosis both to its functional genomic origins and its clinical consequences in humans.

Selective agonist of TRPML2 reveals direct role in chemokine release from innate immune cells

Cytokines and chemokines are produced and secreted by a broad range of immune cells including macrophages. Remarkably, little is known about how these inflammatory mediators are released from the various immune cells. Here, the endolysosomal cation channel TRPML2 is shown to play a direct role in chemokine trafficking and secretion from murine macrophages. To demonstrate acute and direct involvement of TRPML2 in these processes, the first isoform-selective TRPML2 channel agonist was generated, ML2-SA1. ML2-SA1 was not only found to directly stimulate release of the chemokine CCL2 from macrophages but also to stimulate macrophage migration, thus mimicking CCL2 function. Endogenous TRPML2 is expressed in early/recycling endosomes as demonstrated by endolysosomal patch-clamp experimentation and ML2-SA1 promotes trafficking through early/recycling endosomes, suggesting CCL2 being transported and secreted via this pathway. These data provide a direct link between TRPML2 activation, CCL2 release and stimulation of macrophage migration in the innate immune response.

Long Noncoding RNA ANRIL: Lnc-ing Genetic Variation at the Chromosome 9p21 Locus to Molecular Mechanisms of Atherosclerosis

Ever since the first genome-wide association studies (GWAS) on coronary artery disease (CAD), the Chr9p21 risk locus has emerged as a top signal in GWAS of atherosclerotic cardiovascular disease, including stroke and peripheral artery disease. The CAD risk SNPs on Chr9p21 lie within a stretch of 58 kilobases of non-protein-coding DNA, containing the gene body of the long noncoding RNA (lncRNA) antisense non coding RNA in the INK4 locus (ANRIL). How risk is affected by the Chr9p21 locus in molecular detail is a matter of ongoing research. Here we will review recent advances in the understanding that ANRIL serves as a key risk effector molecule of atherogenesis at the locus. One focus of this review is the shift in understanding that genetic variation at Chr9p21 not only affects the abundance of ANRIL, and in some cases expression of the adjacent CDKN2A/B tumor suppressors, but also impacts ANRIL splicing, such that 3′-5′-linked circular noncoding ANRIL RNA species are produced. We describe how the balance of linear and circular ANRIL RNA, determined by the Chr9p21 genotype, regulates molecular pathways and cellular functions involved in atherogenesis. We end with an outlook on how manipulating circular ANRIL abundance may be exploited for therapeutic purposes.

Circular RNAs as Therapeutic Agents and Targets

It has recently been reported that thousands of covalently linked circular RNAs (circRNAs) are expressed from human genomes. circRNAs emerge during RNA splicing. circRNAs are circularized in a reaction termed "backsplicing," whereby the spliceosome fuses a splice donor site in a downstream exon to a splice acceptor site in an upstream exon. Although a young field of research, first studies indicate that backsplicing is not an erroneous reaction of the spliceosome. Instead, circRNAs are produced in cells with high cell-type specificity and can exert biologically meaningful and specific functions. These observations and the finding that circRNAs are stable against exonucleolytic decay are raising the question whether circRNAs may be relevant as therapeutic agents and targets. In this review, we start out with a short introduction into classification, biogenesis and general molecular mechanisms of circRNAs. We then describe reports, where manipulating circRNA abundance has been shown to have therapeutic value in animal disease models in vivo, with a focus on cardiovascular disease (CVD). Starting from existing approaches, we outline particular challenges and opportunities for future circRNA-based therapeutic approaches that exploit stability and molecular effector functions of native circRNAs. We end with considerations which designer functions could be engineered into artificial therapeutic circular RNAs.

Late-pregnancy dysglycemia in obese pregnancies after negative testing for gestational diabetes and risk of future childhood overweight: An interim analysis from a longitudinal mother-child cohort study

BACKGROUND

Maternal pre-conception obesity is a strong risk factor for childhood overweight. However, prenatal mechanisms and their effects in susceptible gestational periods that contribute to this risk are not well understood. We aimed to assess the impact of late-pregnancy dysglycemia in obese pregnancies with negative testing for gestational diabetes mellitus (GDM) on long-term mother-child outcomes.

METHODS AND FINDINGS

The prospective cohort study Programming of Enhanced Adiposity Risk in Childhood-Early Screening (PEACHES) (n = 1,671) enrolled obese and normal weight mothers from August 2010 to December 2015 with trimester-specific data on glucose metabolism including GDM status at the end of the second trimester and maternal glycated hemoglobin (HbA1c) at delivery as a marker for late-pregnancy dysglycemia (HbA1c ≥ 5.7% [39 mmol/mol]). We assessed offspring short- and long-term outcomes up to 4 years, and maternal glucose metabolism 3.5 years postpartum. Multivariable linear and log-binomial regression with effects presented as mean increments (Δ) or relative risks (RRs) with 95% confidence intervals (CIs) were used to examine the association between late-pregnancy dysglycemia and outcomes. Linear mixed-effects models were used to study the longitudinal development of offspring body mass index (BMI) z-scores. The contribution of late-pregnancy dysglycemia to the association between maternal pre-conception obesity and offspring BMI was estimated using mediation analysis. In all, 898 mother-child pairs were included in this unplanned interim analysis. Among obese mothers with negative testing for GDM (n = 448), those with late-pregnancy dysglycemia (n = 135, 30.1%) had higher proportions of excessive total gestational weight gain (GWG), excessive third-trimester GWG, and offspring with large-for-gestational-age birth weight than those without. Besides higher birth weight (Δ 192 g, 95% CI 100-284) and cord-blood C-peptide concentration (Δ 0.10 ng/ml, 95% CI 0.02-0.17), offspring of these women had greater weight gain during early childhood (Δ BMI z-score per year 0.18, 95% CI 0.06-0.30, n = 262) and higher BMI z-score at 4 years (Δ 0.58, 95% CI 0.18-0.99, n = 43) than offspring of the obese, GDM-negative mothers with normal HbA1c values at delivery. Late-pregnancy dysglycemia in GDM-negative mothers accounted for about one-quarter of the association of maternal obesity with offspring BMI at age 4 years (n = 151). In contrast, childhood BMI z-scores were not affected by a diagnosis of GDM in obese pregnancies (GDM-positive: 0.58, 95% CI 0.36-0.79, versus GDM-negative: 0.62, 95% CI 0.44-0.79). One mechanism triggering late-pregnancy dysglycemia in obese, GDM-negative mothers was related to excessive third-trimester weight gain (RR 1.72, 95% CI 1.12-2.65). Furthermore, in the maternal population, we found a 4-fold (RR 4.01, 95% CI 1.97-8.17) increased risk of future prediabetes or diabetes if obese, GDM-negative women had a high versus normal HbA1c at delivery (absolute risk: 43.2% versus 10.5%). There is a potential for misclassification bias as the predominantly used GDM test procedure changed over the enrollment period. Further studies are required to validate the findings and elucidate the possible third-trimester factors contributing to future mother-child health status.

CONCLUSIONS

Findings from this interim analysis suggest that offspring of obese mothers treated because of a diagnosis of GDM appeared to have a better BMI outcome in childhood than those of obese mothers who-following negative GDM testing-remained untreated in the last trimester and developed dysglycemia. Late-pregnancy dysglycemia related to uncontrolled weight gain may contribute to the development of child overweight and maternal diabetes. Our data suggest that negative GDM testing in obese pregnancies is not an "all-clear signal" and should not lead to reduced attention and risk awareness of physicians and obese women. Effective strategies are needed to maintain third-trimester glycemic and weight gain control among otherwise healthy obese pregnant women.

Molecular functions and specific roles of circRNAs in the cardiovascular system

As part of the superfamily of long noncoding RNAs, circular RNAs (circRNAs) are emerging as a new type of regulatory molecules that partake in gene expression control. Here, we review the current knowledge about circRNAs in cardiovascular disease. CircRNAs are not only associated with different types of cardiovascular disease, but they have also been identified as intracellular effector molecules for pathophysiological changes in cardiovascular tissues, and as cardiovascular biomarkers. This evidence is put in the context of the current understanding of general circRNA biogenesis and of known interactions of circRNAs with DNA, RNA, and proteins.

CXCL8 hyper-signaling in the aortic abdominal aneurysm

There are indications for elevated CXCL8 levels in abdominal aortic aneurysm disease (AAA). CXCL8 is concurrently involved in neutrophil-mediated inflammation and angiogenesis, two prominent and distinctive characteristics of AAA. As such we considered an evaluation of a role for CXCL8 in AAA progression relevant. ELISA's, real time PCR and array analysis were used to explore CXCL8 signaling in AAA wall samples. A role for CXCL8 in AAA disease was tested through the oral CXCR1/2 antagonist DF2156A in the elastase model of AAA disease. There is an extreme disparity in aortic wall CXCL8 content between AAA and aortic atherosclerotic disease (median [IQR] aortic wall CXCL8 content: 425 [141-1261] (AAA) vs. 23 [2.8-89] (atherosclerotic aorta) µg/g protein (P < 1 · 10^-14)), and abundant expression of the CXCR1 and 2 receptors in AAA. Array analysis followed by pathway analysis showed that CXCL8 hyper-expression in AAA is followed increased by IL-8 signaling (Z-score for AAA vs. atherosclerotic control: 2.97, p < 0.0001). Interference with CXCL8 signaling through DF2156A fully abrogated AAA formation and prevented matrix degradation in the murine elastase model of AAA disease (p < 0.001). CXCL8-signaling is a prominent and distinctive feature of AAA, interference with the pathway constitutes a promising target for medical stabilization of AAA.

Poly(lactic-co-glycolic) Acid as a Slow-Release Drug-Carrying Matrix for Methotrexate Coated onto Intraocular Lenses to Conquer Posterior Capsule Opacification

PURPOSE

Posterior capsule opacification (PCO) still represents the main long-term complication of cataract surgery. Research into pharmacologic PCO prophylaxis is extensive. One promising candidate drug is methotrexate (MTX). Our aim is to determine the in vitro feasibility of MTX-loaded poly(lactic-co-glycolic) (PLGA) biomatrices sprayed on intraocular lenses (IOLs) as a drug-delivery implant.

METHODS

Hydrophilic and hydrophobic acrylic IOLs were spray-coated with MTX-loaded PLGA. Unsprayed, solvent only, and solvent-PLGA-sprayed IOLs served as controls. All IOLs were evaluated for their growth-inhibiting properties in an in vitro anterior segment model and the ex vivo human capsular bag. The release kinetics of MTX from the IOLs was determined. The toxicity of MTX on corneal endothelial cells was evaluated by using a dye reduction colorimetric assay. MTX was also used in a scratch assay.

RESULTS

MTX-PLGA-IOL showed a significant difference in cell proliferation and migration compared with all controls in the anterior segment model (p < 0.001) and in the human capsular bag model (p = 0.04). No difference in viability was observed on corneal endothelial cells (p = 0.43; p = 0.61). MTX significantly inhibited cells in the scratch assay (p = 0.02). At all measured points, the released MTX dose remained above EC50 and below the toxic dose for the endothelium.

CONCLUSIONS

In view of the strong inhibition of PCO in vitro with the lack of toxic effects on a corneal cell line, MTX encapsulating microspheres seem to be a promising method for modifying IOL.

Serum Markers of Inflammation Mediate the Positive Association Between Neuroticism and Depression

Background: The personality trait neuroticism has been implicated in a poor response to stress, may relate to increased concentrations of cytokines and the development of depression. Inflammatory mechanisms may also be associated with the onset, severity and symptoms of depression. Both are related to poor antidepressant treatment outcome. Therefore, mediators of inflammation may bridge the relationship between neuroticism and depression. Methods: To disentangle these interrelationships, the associations between neuroticism (according to NEO-PIR-N), depressive symptoms (BDI-II scores) and serum levels of hsCRP, TNF-α, IFN-γ, IL-2, IL-4, IL-5, IL-10, IL-12, IL-13, GM-CSF were investigated in a group of 212 participants, consisting of 37 depressed and 175 non-depressed subjects. A mediation model was used to investigate whether the impact of neuroticism on depressive symptoms may be mediated by cytokines. Results: Regression analyses revealed that IFN-γ, IL-5, and IL-12-levels, but none of the anti-inflammatory cytokines, were associated with the overall neuroticism score and several of the cytokines were related to the different facets of neuroticism. TNF-α, IFN-γ, IL-5, IL-12, and IL-13 were further related to the severity of depressive symptoms, as well as the somatic-affective and the cognitive dimensions of depression. Pro-inflammatory IFN-γ, IL-5 and IL-12 were identified as mediators of the positive prediction of depression severity by the degree of neuroticism. Conclusions: The current findings demonstrate that conditions related to long-term stress, such as depression and high neuroticism, are related to an up-regulation of inflammatory agents. Neuroticism may increase stress perception and, thus, increase the production of pro-inflammatory messenger molecules which are involved in the development of depression. This evidence may contribute to future anti-inflammatory interventions, particularly in subjects with high neuroticism who are at risk for developing depression. Furthermore, depressed patients with high neuroticism and cytokine levels may require early escalations in the intensity of treatment, along with additional therapeutic elements to increase the rate of treatment success.

CD70 limits atherosclerosis and promotes macrophage function

The costimulatory molecule CD70 is expressed on activated immune cells and is known to modulate responses of T, B, and NK cells via its receptor CD27. Until now, there is only limited data describing the role of CD70 in atherosclerosis. We observed that ruptured human carotid atherosclerotic plaques displayed higher CD70 expression than stable carotid atherosclerotic plaques, and that CD70 expression in murine atheroma localized to macrophages. Lack of CD70 impaired the inflammatory capacity (e. g. reactive oxygen species and nitric oxide production) of bone marrow-derived macrophages, increased both M1-like and M2-like macrophage markers, and rendered macrophages meta-bolically inactive and prone to apoptosis. Moreover, CD70-deficient macrophages expressed diminished levels of scavenger receptors and ABC-transporters, impairing uptake of oxidised low-density lipoprotein (oxLDL) and cholesterol efflux, respectively. Hyperlipidaemic Apoe −/− mice reconstituted with CD70-deficient bone marrow displayed a profound increase in necrotic core size, plaque area, and number of lesional macrophages as compared to mice receiving control bone marrow. Accordingly, 18 week-old, chow diet-fed CD70-deficient Apoe−/−mice displayed larger atheroma characterised by lower cellularity and more advanced plaque phenotype than Apoe−/− mice. In conclusion, CD70 promotes macrophage function and viability and is crucial for effective phagocytosis and efflux of oxLDL. Deficiency in CD70 results in more advanced atheroma. Our data suggest that CD70 mitigates atherosclerosis at least in part by modulating macrophage function.

Note: The review process for this manuscript was fully handled by G. Y. H. Lip, Editor in Chief.

Supplementary Material to this article is available online at www.thrombosis-online.com.

Molecular Fingerprint for Terminal Abdominal Aortic Aneurysm Disease

Background

Clinical decision making in abdominal aortic aneurysms (AAA) relies completely on diameter. At this point, improved decision tools remain an unmet medical need. Our goal was to identify changes at the molecular level specifically leading up to AAA rupture.

Methods and Results

Aortic wall tissue specimens were collected during open elective (eAAA; n=31) or emergency repair of ruptured AAA (rAAA; n=17), and gene expression was investigated using microarrays. Identified candidate genes were validated with quantitative real‐time polymerase chain reaction in an independent sample set (eAAA: n=46; rAAA: n=18). Two gene sets were identified, 1 set containing 5 genes linked to terminal progression, that is, positively associated with progression of larger AAA, and with rupture (HILPDA,ANGPTL4,LOX,SRPX2,FCGBP), and a second set containing 5 genes exclusively upregulated in rAAA (ADAMTS9,STC1,GFPT2,GAL3ST4,CCL4L1). Genes in both sets essentially associated with processes related to impaired tissue remodeling, such as angiogenesis and adipogenesis. In gene expression experiments we were able to show that upregulated gene expression for identified candidate genes is unique for AAA. Functionally, the selected upregulated factors converge at processes coordinated by the canonical HIF‐1α signaling pathway and are highly expressed in fibroblasts but not inflammatory cells of the aneurysmatic wall. Histological quantification of angiogenesis and exploration of the HIF‐1α network in rAAA versus eAAA shows enhanced microvessel density but also clear activation of the HIF‐1α network in rAAA.

Conclusions

Our study shows a specific molecular fingerprint for terminal AAA disease. These changes appear to converge at activation of HIF‐1α signaling in mesenchymal cells. Aspects of this cascade might represent targets for rupture risk assessment.

Revisiting biomarker discovery by plasma proteomics

Clinical analysis of blood is the most widespread diagnostic procedure in medicine, and blood biomarkers are used to categorize patients and to support treatment decisions. However, existing biomarkers are far from comprehensive and often lack specificity and new ones are being developed at a very slow rate. As described in this review, mass spectrometry (MS)-based proteomics has become a powerful technology in biological research and it is now poised to allow the characterization of the plasma proteome in great depth. Previous "triangular strategies" aimed at discovering single biomarker candidates in small cohorts, followed by classical immunoassays in much larger validation cohorts. We propose a "rectangular" plasma proteome profiling strategy, in which the proteome patterns of large cohorts are correlated with their phenotypes in health and disease. Translating such concepts into clinical practice will require restructuring several aspects of diagnostic decision-making, and we discuss some first steps in this direction.

Quantitative trait locus mapping in mice identifies phospholipase Pla2g12a as novel atherosclerosis modifier

BACKGROUND AND AIMS

In a previous work, a female-specific atherosclerosis risk locus on chromosome (Chr) 3 was identified in an intercross of atherosclerosis-resistant FVB and atherosclerosis-susceptible C57BL/6 (B6) mice on the LDL-receptor deficient (Ldlr^-/-) background. It was the aim of the current study to identify causative genes at this locus.

METHODS

We established a congenic mouse model, where FVB.Chr3^B6/B6 mice carried an 80 Mb interval of distal Chr3 on an otherwise FVB.Ldlr^-/- background, to validate the Chr3 locus. Candidate genes were identified using genome-wide expression analyses. Differentially expressed genes were validated using quantitative PCRs in F0 and F2 mice and their functions were investigated in pathophysiologically relevant cells.

RESULTS

Fine-mapping of the Chr3 locus revealed two overlapping, yet independent subloci for female atherosclerosis susceptibility: when transmitted by grandfathers to granddaughters, the B6 risk allele increased atherosclerosis and downregulated the expression of the secreted phospholipase Pla2g12a (2.6 and 2.2 fold, respectively); when inherited by grandmothers, the B6 risk allele induced vascular cell adhesion molecule 1 (Vcam1). Down-regulation of Pla2g12a and up-regulation of Vcam1 were validated in female FVB.Chr3^B6/B6 congenic mice, which developed 2.5 greater atherosclerotic lesions compared to littermate controls (p=0.039). Pla2g12a was highly expressed in aortic endothelial cells in vivo, and knocking-down Pla2g12a expression by RNAi in cultured vascular endothelial cells or macrophages increased their adhesion to ECs in vitro.

CONCLUSIONS

Our data establish Pla2g12a as an atheroprotective candidate gene in mice, where high expression levels in ECs and macrophages may limit the recruitment and accumulation of these cells in nascent atherosclerotic lesions.

Adventitial adipogenic degeneration is an unidentified contributor to aortic wall weakening in the abdominal aortic aneurysm

OBJECTIVE

The processes driving human abdominal aortic aneurysm (AAA) progression are not fully understood. Although antiinflammatory and proteolytic strategies effectively quench aneurysm progression in preclinical models, so far all clinical interventions failed. These observations hint at an incomplete understanding of the processes involved in AAA progression and rupture. Interestingly, strong clinical and molecular associations exist between popliteal artery aneurysms (PAAs) and AAAs; however, PAAs have an extremely low propensity to rupture. We thus reasoned that differences between these aneurysms may provide clues toward (auxiliary) processes involved in AAA-related wall debilitation. A better understanding of the pathophysiologic processes driving AAA growth can contribute to pharmaceutical treatments in the future.

METHODS

Aneurysmal wall samples were collected during open elective and emergency repair. Control perirenal aorta was obtained during kidney transplantation, and reference popliteal tissue obtained from the anatomy department. This study incorporates various techniques including (immuno)histochemistry, Western Blot, quantitative polymerase chain reaction, microarray, and cell culture.

RESULTS

Histologic evaluation of AAAs, PAAs, and control aorta shows extensive medial (PAA) and transmural fibrosis (AAA), and reveals abundant adventitial adipocytes aggregates as an exclusive phenomenon of AAAs (P < .001). Quantitative polymerase chain reaction, immunohistochemistry, Western blotting, and microarray analysis showed enrichment of adipogenic mediators (C/EBP family P = .027; KLF5 P < .000; and peroxisome proliferator activated receptor-γ, P = .032) in AAA tissue. In vitro differentiation tests indicated a sharply increased adipogenic potential of AAA adventitial mesenchymal cells (P < .0001). Observed enrichment of adipocyte-related genes and pathways in ruptured AAA (P < .0003) supports an association between the extent of fatty degeneration and rupture.

CONCLUSIONS

This translational study identifies extensive adventitial fatty degeneration as an ignored and distinctive feature of AAA disease. Enrichment of adipocyte genesis and adipocyte-related genes in ruptured AAA point to an association between the extent of fatty degeneration and rupture. This observation may (partly) explain the failure of medical therapy and could provide a lead for pharmaceutical alleviation of AAA progression.

Cathepsin S increases tau oligomer formation through limited cleavage, but only IL-6, not cathespin S serum levels correlate with disease severity in the neurodegenerative tauopathy progressive supranuclear palsy

Limited cleavage promotes the aggregation propensity of protein tau in neurodegenerative tauopathies. Cathepsin S (CatS) is overexpressed in brains of patients suffering from tauopathies such as Alzheimer's disease (AD). Furthermore, CatS serum levels correlate with survival in the elderly. The current study investigates whether limited cleavage by CatS promotes tau aggregation, and whether CatS serum levels may correlate with disease severity in tauopathies. Oligomer formation of fluorescently labeled protein tau was monitored by single particle fluorescence spectroscopy after coincubation with CatS. Tau cleavage patterns were investigated by SDS-PAGE. For serum analyses, samples were collected from 42 patients with probable progressive supranuclear palsy (PSP) according to NINDS-PSP criteria. Disease severity was assessed by PSP rating scale (PSP-RS), PSP staging system (PSP-S) and Schwab and England Activities of Daily Living (SEADL). CatS, cystatin C (CysC) and interleukin 6 (IL-6) serum levels were determined by ELISA, ECLIA and turbidimetry, respectively. SDS-PAGE demonstrated a distinct cleavage pattern of protein tau after coincubation with CatS. Furthermore, tau oligomer formation was increased 2.4-fold (p < 0.05) after limited cleavage. Serum CatS and CysC levels did not correlate with disease severity in PSP. Of note, IL-6 correlated with PSP-S (r = 0.41; 95% CI 0.11-0.65; p = 0.008), SEADL (r = -0.37; 95% CI -0.61 to -0.06; p = 0.017) and the history and gait/midline subdomains of the PSP-RS. While CatS facilitates tau aggregation in vitro, serum levels of CatS appear not to correlate with disease severity. The observed correlation of IL-6 with disease severity warrants further investigation of inflammatory markers in PSP.

Vascular CXCR4 Limits Atherosclerosis by Maintaining Arterial Integrity: Evidence From Mouse and Human Studies

BACKGROUND

The CXCL12/CXCR4 chemokine ligand/receptor axis controls (progenitor) cell homeostasis and trafficking. So far, an atheroprotective role of CXCL12/CXCR4 has only been implied through pharmacological intervention, in particular, because the somatic deletion of the CXCR4 gene in mice is embryonically lethal. Moreover, cell-specific effects of CXCR4 in the arterial wall and underlying mechanisms remain elusive, prompting us to investigate the relevance of CXCR4 in vascular cell types for atheroprotection.

METHODS

We examined the role of vascular CXCR4 in atherosclerosis and plaque composition by inducing an endothelial cell (BmxCreER^T2-driven)-specific or smooth muscle cell (SMC, SmmhcCreER^T2- or TaglnCre-driven)-specific deficiency of CXCR4 in an apolipoprotein E-deficient mouse model. To identify underlying mechanisms for effects of CXCR4, we studied endothelial permeability, intravital leukocyte adhesion, involvement of the Akt/WNT/β-catenin signaling pathway and relevant phosphatases in VE-cadherin expression and function, vascular tone in aortic rings, cholesterol efflux from macrophages, and expression of SMC phenotypic markers. Finally, we analyzed associations of common genetic variants at the CXCR4 locus with the risk for coronary heart disease, along with CXCR4 transcript expression in human atherosclerotic plaques.

RESULTS

The cell-specific deletion of CXCR4 in arterial endothelial cells (n=12-15) or SMCs (n=13-24) markedly increased atherosclerotic lesion formation in hyperlipidemic mice. Endothelial barrier function was promoted by CXCL12/CXCR4, which triggered Akt/WNT/β-catenin signaling to drive VE-cadherin expression and stabilized junctional VE-cadherin complexes through associated phosphatases. Conversely, endothelial CXCR4 deficiency caused arterial leakage and inflammatory leukocyte recruitment during atherogenesis. In arterial SMCs, CXCR4 sustained normal vascular reactivity and contractile responses, whereas CXCR4 deficiency favored a synthetic phenotype, the occurrence of macrophage-like SMCs in the lesions, and impaired cholesterol efflux. Regression analyses in humans (n=259 796) identified the C-allele at rs2322864 within the CXCR4 locus to be associated with increased risk for coronary heart disease. In line, C/C risk genotype carriers showed reduced CXCR4 expression in carotid artery plaques (n=188), which was furthermore associated with symptomatic disease.

CONCLUSIONS

Our data clearly establish that vascular CXCR4 limits atherosclerosis by maintaining arterial integrity, preserving endothelial barrier function, and a normal contractile SMC phenotype. Enhancing these beneficial functions of arterial CXCR4 by selective modulators might open novel therapeutic options in atherosclerosis.

Whole genome sequencing of Brucella melitensis isolated from 57 patients in Germany reveals high diversity in strains from Middle East

Brucellosis, a worldwide common bacterial zoonotic disease, has become quite rare in Northern and Western Europe. However, since 2014 a significant increase of imported infections caused by Brucella (B.) melitensis has been noticed in Germany. Patients predominantly originated from Middle East including Turkey and Syria. These circumstances afforded an opportunity to gain insights into the population structure of Brucella strains. Brucella-isolates from 57 patients were recovered between January 2014 and June 2016 with culture confirmed brucellosis by the National Consultant Laboratory for Brucella. Their whole genome sequences were generated using the Illumina MiSeq platform. A whole genome-based SNP typing assay was developed in order to resolve geographically attributed genetic clusters. Results were compared to MLVA typing results, the current gold-standard of Brucella typing. In addition, sequences were examined for possible genetic variation within target regions of molecular diagnostic assays. Phylogenetic analyses revealed spatial clustering and distinguished strains from different patients in either case, whereas multiple isolates from a single patient or technical replicates showed identical SNP and MLVA profiles. By including WGS data from the NCBI database, five major genotypes were identified. Notably, strains originating from Turkey showed a high diversity and grouped into seven subclusters of genotype II. MLVA analysis congruently clustered all isolates and predominantly matched the East Mediterranean genetic clade. This study confirms whole-genome based SNP-analysis as a powerful tool for accurate typing of B. melitensis. Furthermore it allows special allocation and therefore provides useful information on the geographic origin for trace-back analysis. However, the lack of reliable metadata in public databases often prevents a resolution below geographic regions or country levels and corresponding precise trace-back analysis. Once this obstacle is resolved, WGS-derived bacterial typing adds an important method to complement epidemiological surveys during outbreak investigations. This is the first report of a detailed genetic investigation of an extensive collection of B. melitensis strains isolated from human cases in Germany.

Genome-wide meta-analysis identifies novel loci of plaque burden in carotid artery

BACKGROUND AND AIMS

Carotid artery plaque is an established marker of subclinical atherosclerosis and common patho-mechanisms with coronary artery disease (CAD) are hypothesized. We aimed to identify genetic variants associated with carotid plaque and to examine the potential shared genetic basis with CAD.

METHODS

After investigating the reliability of plaque detection, we performed a genome-wide meta-association study in two independent cohorts (LIFE-Adult, n = 4037 and LIFE-Heart, n = 3152) for carotid plaque score (PS), defined as the sum of the plaque load of common carotid artery and carotid bulb. Further, we analyzed whether previously reported CAD and stroke loci were also associated with PS.

RESULTS

We identified two loci with genome-wide significance for PS. One locus is the known CAD-locus at chromosome 9p21 (lead SNP rs9644862, p = 8.73 × 10^-12). We also describe a novel locus on chromosome 10q24 within the SFXN2 gene as the most probable candidate (lead SNP rs2902548, p = 1.97 × 10^-8). In addition, 17 out of 58 known CAD loci and six of 17 known stroke loci were associated with PS at a nominal level of significance.

CONCLUSIONS

We showed that PS is a reliable trait to analyze genetics of atherosclerosis. Two new loci of genome-wide significant association with PS were found. The observed non-random overlap of CAD and PS associations strengthens the hypothesis of a shared genetic basis for these atherosclerotic manifestations.

Methylated free-circulating HPP1 DNA is an early response marker in patients with metastatic colorectal cancer

Detection of methylated free-circulating DNA (mfcDNA) for hyperplastic polyposis 1 (HPP1) in blood is correlated with a poor prognosis for patients with metastatic colorectal cancers (mCRC). Here, we analyzed the plasma levels of HPP1 mfcDNA in mCRC patients treated with a combination therapy containing a fluoropyrimidine, oxaliplatin and bevacizumab to test whether HPP1 mfcDNA is a suitable prognostic and response biomarker. From 467 patients of the prospective clinical study AIO-KRK-0207, mfcDNA was isolated from plasma samples at different time points and bisulfite-treated mfcDNA was quantified using methylation specific PCR. About 337 of 467 patients had detectable levels for HPP1 mfcDNA before start of treatment. The detection was significantly correlated with poorer overall survival (OS) (HR = 1.86; 95%CI 1.37-2.53). About 2-3 weeks after the first administration of combination chemotherapy, HPP1 mfcDNA was reduced to non-detectable levels in 167 of 337 patients. These patients showed a better OS compared with patients with continued detection of HPP1 mfcDNA (HR HPP1(sample 1: pos/ sample 2: neg) vs. HPP1(neg/neg) = 1.41; 95%CI 1.00-2.01, HPP1(neg,pos/pos) vs. HPP1(neg/neg) = 2.60; 95%CI 1.86-3.64). Receiver operating characteristic analysis demonstrated that HPP1 mfcDNA discriminates well between patients who do (not) respond to therapy according to the radiological staging after 12 or 24 weeks (AUC = 0.77 or 0.71, respectively). Detection of HPP1 mfcDNA can be used as a prognostic marker and an early marker for response (as early as 3-4 weeks after start of treatment compared with radiological staging after 12 or 24 weeks) to identify patients who will likely benefit from a combination chemotherapy with bevacizumab.

Alteration of Multiple Leukocyte Gene Expression Networks is Linked with Magnetic Resonance Markers of Prognosis After Acute ST-Elevation Myocardial Infarction

Prognostic relevant pathways of leukocyte involvement in human myocardial ischemic-reperfusion injury are largely unknown. We enrolled 136 patients with ST-elevation myocardial infarction (STEMI) after primary angioplasty within 12 h after onset of symptoms. Following reperfusion, whole blood was collected within a median time interval of 20 h (interquartile range: 15-25 h) for genome-wide gene expression analysis. Subsequent CMR scans were performed using a standard protocol to determine infarct size (IS), area at risk (AAR), myocardial salvage index (MSI) and the extent of late microvascular obstruction (lateMO). We found 398 genes associated with lateMO and two genes with IS. Neither AAR, nor MSI showed significant correlations with gene expression. Genes correlating with lateMO were strongly related to several canonical pathways, including positive regulation of T-cell activation (p = 3.44 × 10^-5), and regulation of inflammatory response (p = 1.86 × 10^-3). Network analysis of multiple gene expression alterations associated with larger lateMO identified the following functional consequences: facilitated utilisation and decreased concentration of free fatty acid, repressed cell differentiation, enhanced phagocyte movement, increased cell death, vascular disease and compensatory vasculogenesis. In conclusion, the extent of lateMO after acute, reperfused STEMI correlated with altered activation of multiple genes related to fatty acid utilisation, lymphocyte differentiation, phagocyte mobilisation, cell survival, and vascular dysfunction.

Adam17 Deficiency Promotes Atherosclerosis by Enhanced TNFR2 Signaling in Mice

OBJECTIVE

ADAM17 (a disintegrin and metalloproteinase 17) is a sheddase releasing different types of membrane-bound proteins, including adhesion molecules, cytokines, and their receptors as well as inflammatory mediators. Because these substrates modulate important mechanisms of atherosclerosis, we hypothesized that ADAM17 might be involved in the pathogenesis of this frequent disease.

APPROACH AND RESULTS

Because Adam17-knockout mice are not viable, we studied the effect of Adam17 deficiency on atherosclerosis in Adam17 hypomorphic mice (Adam17^ex/ex), which have low residual Adam17 expression. To induce atherosclerosis, mice were crossed onto the low-density lipoprotein receptor (Ldlr)-deficient background. We found that Adam17^ex/ex.Ldlr^-/- mice developed ≈1.5-fold larger atherosclerotic lesions, which contained more macrophages and vascular smooth muscle cells than wild-type littermate controls (Adam17^wt/wt.Ldlr^-/-). Reduced Adam17-mediated shedding led to significantly increased protein levels of membrane-resident TNFα (tumor necrosis factor) and TNFR2 (tumor necrosis factor receptor 2), resulting in a constitutive activation of TNFR2 signaling. At the same time, Adam17 deficiency promoted proatherosclerotic cellular functions, such as increased proliferation and reduced apoptosis in cultured macrophages and vascular smooth muscle cells and increased adhesion of macrophages to vascular endothelial cells. Because siRNA (small interfering RNA)-mediated knockdown of Tnfr2 rescued from aberrant proliferation and from misregulation of apoptosis in Adam17-depleted cells, our data indicate that TNFR2 is an important effector of ADAM17 in our mouse model.

CONCLUSIONS

Our results provide evidence for an atheroprotective role of ADAM17, which might be mediated by cleaving membrane-bound TNFα and TNFR2, thereby preventing overactivation of endogenous TNFR2 signaling in cells of the vasculature.

Changes of bivalent chromatin coincide with increased expression of developmental genes in cancer

Bivalent (poised or paused) chromatin comprises activating and repressing histone modifications at the same location. This combination of epigenetic marks at promoter or enhancer regions keeps genes expressed at low levels but poised for rapid activation. Typically, DNA at bivalent promoters is only lowly methylated in normal cells, but frequently shows elevated methylation levels in cancer samples. Here, we developed a universal classifier built from chromatin data that can identify cancer samples solely from hypermethylation of bivalent chromatin. Tested on over 7,000 DNA methylation data sets from several cancer types, it reaches an AUC of 0.92. Although higher levels of DNA methylation are often associated with transcriptional silencing, counter-intuitive positive statistical dependencies between DNA methylation and expression levels have been recently reported for two cancer types. Here, we re-analyze combined expression and DNA methylation data sets, comprising over 5,000 samples, and demonstrate that the conjunction of hypermethylation of bivalent chromatin and up-regulation of the corresponding genes is a general phenomenon in cancer. This up-regulation affects many developmental genes and transcription factors, including dozens of homeobox genes and other genes implicated in cancer. Thus, we reason that the disturbance of bivalent chromatin may be intimately linked to tumorigenesis.

Impact of Serum Cytokine Levels on EEG-Measured Arousal Regulation in Patients with Major Depressive Disorder and Healthy Controls

BACKGROUND

In major depressive disorder (MDD), findings include hyperstable regulation of brain arousal measured by electroencephalography (EEG) vigilance analysis and alterations in serum levels of cytokines. It is also known that cytokines affect sleep-wake regulation. This study investigated the relationship between cytokines and EEG vigilance in participants with MDD and nondepressed controls, and the influence of cytokines on differences in vigilance between the two groups.

METHODS

In 60 patients with MDD and 129 controls, 15-min resting-state EEG recordings were performed and vigilance was automatically assessed with the VIGALL 2.0 (Vigilance Algorithm Leipzig). Serum levels of the wakefulness-promoting cytokines interleukin (IL)-4, IL-10, IL-13 and somnogenic cytokines tumor necrosis factor-α, interferon-x03B3; and IL-2 were measured prior to the EEG.

RESULTS

Summed wakefulness-promoting cytokines, but not somnogenic cytokines, were significantly associated with the time course of EEG vigilance in the MDD group only. In both groups, IL-13 was significantly associated with the course of EEG vigilance. In MDD compared to controls, a hyperstable EEG vigilance regulation was found, significant for group and group × time course interaction. After controlling for wakefulness-promoting cytokines, differences in vigilance regulation between groups remained significant.

CONCLUSIONS

The present study demonstrated a relationship between wakefulness-promoting cytokines and objectively measured EEG vigilance as an indicator for brain arousal. Altered brain arousal regulation in MDD gives support for future evaluation of vigilance measures as a biomarker in MDD. Since interactions between cytokines and EEG vigilance only moderately differed between the groups and cytokine levels could not explain the group differences in EEG vigilance regulation, cytokines and brain arousal regulation are likely to be associated with MDD in independent ways.

Epigenetic Signatures at AQP3 and SOCS3 Engage in Low-Grade Inflammation across Different Tissues

BACKGROUND

Elevated levels of C-reactive protein (CRP, determined by a high-sensitivity assay) indicate low-grade inflammation which is implicated in many age-related disorders. Epigenetic studies on CRP might discover molecular mechanisms underlying CRP regulation. We aimed to identify DNA methylation sites related to CRP concentrations in cells and tissues regulating low-grade inflammation.

RESULTS

Genome-wide DNA methylation was measured in peripheral blood in 1,741 participants of the KORA F4 study using Illumina HumanMethylation450 BeadChip arrays. Four CpG sites (located at BCL3, AQP3, SOCS3, and cg19821297 intergenic at chromosome 19p13.2, P ≤ 1.01E-07) were significantly hypomethylated at high CRP concentrations independent of various confounders including age, sex, BMI, smoking, and white blood cell composition. Findings were not sex-specific. CRP-related top genes were enriched in JAK/STAT pathways (Benjamini-Hochberg corrected P < 0.05). Results were followed-up in three studies using DNA from peripheral blood (EPICOR, n = 503) and adipose tissue (TwinsUK, n = 368) measured as described above and from liver tissue (LMU liver cohort, n = 286) measured by MALDI-TOF mass spectrometry using EpiTYPER. CpG sites at the AQP3 locus (significant p-values in peripheral blood = 1.72E-03 and liver tissue = 1.51E-03) and the SOCS3 locus (p-values in liver < 2.82E-05) were associated with CRP in the validation panels.

CONCLUSIONS

Epigenetic modifications seem to engage in low-grade inflammation, possibly via JAK/STAT mediated pathways. Results suggest a shared relevance across different tissues at the AQP3 locus and highlight a role of DNA methylation for CRP regulation at the SOCS3 locus.

Serum concentrations of TNF-α and its soluble receptors during psychotherapy in German soldiers suffering from combat-related PTSD

BACKGROUND

Changes in serum concentrations of tumor necrosis factor-α (TNF-α) and its soluble receptors (sTNF-R) p55 and p75 have been shown to be associated with various psychiatric treatments.

SUBJECTS AND METHODS

Before and after treatment, serum levels of TNF-α, sTNF-R p55 and sTNF-R p75 were measured in 38 German soldiers who had been deployed abroad and suffered from combat-related post-traumatic stress disorder (PTSD). Patients were randomized either to inpatient psychotherapy (N=21) including eye movement desensitization and reprocessing (EMDR) or to outpatient clinical management (N=17). Symptoms of PTSD were measured using the Post-traumatic Stress Diagnostic Scale (PDS).

RESULTS

The PDS score significantly decreased across time in both groups. Serum concentrations of TNF-α increased, while sTNF-R p55 and sTNF-R p75 levels decreased significantly. After the treatment period, we could not detect any significant difference regarding TNF-α, sTNF-R p55 or sTNF-R p75 levels between the inpatient psychotherapy group and the outpatient clinical management control group.

CONCLUSIONS

This relatively small clinical study suggests that specific inpatient psychotherapy but also non-specific supportive outpatient treatment for PTSD are associated with changes in the TNF-α system. This may represent an immunological effects or side effects of psychotherapy.

Circular non-coding RNA ANRIL modulates ribosomal RNA maturation and atherosclerosis in humans

Circular RNAs (circRNAs) are broadly expressed in eukaryotic cells, but their molecular mechanism in human disease remains obscure. Here we show that circular antisense non-coding RNA in the INK4 locus (circANRIL), which is transcribed at a locus of atherosclerotic cardiovascular disease on chromosome 9p21, confers atheroprotection by controlling ribosomal RNA (rRNA) maturation and modulating pathways of atherogenesis. CircANRIL binds to pescadillo homologue 1 (PES1), an essential 60S-preribosomal assembly factor, thereby impairing exonuclease-mediated pre-rRNA processing and ribosome biogenesis in vascular smooth muscle cells and macrophages. As a consequence, circANRIL induces nucleolar stress and p53 activation, resulting in the induction of apoptosis and inhibition of proliferation, which are key cell functions in atherosclerosis. Collectively, these findings identify circANRIL as a prototype of a circRNA regulating ribosome biogenesis and conferring atheroprotection, thereby showing that circularization of long non-coding RNAs may alter RNA function and protect from human disease.

Thyroid Hormones and Vitamin D in Patients with Breast Cancer with Mutations in BRCA1 or BRCA2 Genes

AIM

The thyroid hormones free triiodothyronine (fT3), free thyroxine (fT4), thyroid-stimulating hormone (TSH) and vitamin D seem to be involved in the process of differentiation and proliferation of breast tissue. Little is known about these factors in breast cancer 1 and 2 (BRCA1/BRCA2)-mutation carriers with breast cancer (BC). The purpose of this investigation was to evaluate the association of thyroid gland function and vitamin D with BC in patients with BRCA mutations.

PATIENTS AND METHODS

At the Department of Hereditary Breast and Ovarian Cancer of the Ludwig Maximilian University Hospital of Munich, 40 patients with BC (10 patients with mutations in the BRCA1 gene, 10 with mutations in the BRCA2 gene, and 20 without mutations, as control group) were selected for analysis of the following parameters: fT3, fT4, TSH and vitamin D. The primary diagnosis was made between 21 and 62 years of age. The patients were matched by age. Anamnestic data were evaluated concerning disorders of the thyroid gland and primary BC diagnosis.

RESULTS

In patients with BC, BRCA mutations are not associated with thyroidal dysfunctions. A significantly increased level of vitamin D in BRCA2-mutation carriers compared to those without mutation (p=0.02) was detected. The grade of the tumors in the BRCA2 group was better than in those with mutation. BRCA1-mutation carriers had an increased incidence of primary BC diagnosis during pregnancy (30% vs. 0%) in comparison to those without mutation.

CONCLUSION

No association between the thyroid hormones and BC in BRCA1/2-mutation carriers was found. Vitamin D was significantly elevated in BRCA2-mutation carriers and the observation of a better tumor grade in this group could be consistent with the ability of vitamin D to inhibit growth and induce differentiation.

Pro- and anti-inflammatory cytokines, but not CRP, are inversely correlated with severity and symptoms of major depression

To clarify findings of elevated cytokine levels in major depression (MD), this study aimed to investigate the relationship between serum levels of cytokines, symptoms of MD and antidepressant treatment outcome. At baseline (T0) and 4 weeks following initiation of antidepressant treatment (T1), levels of tumor necrosis factor (TNF)-α, interferon (IFN)-γ, interleukin (IL)-2, IL-4, IL-5, IL-10, IL-12, IL-13, granulocyte-macrophage-colony-stimulating-factor (GM-CSF), CRP and depression ratings HAMD-17 and BDI-II were assessed in 30 patients with MD and 30 age-and sex-matched controls. At T0, in the patient group, cytokines, but not CRP, negatively correlated with individual BDI-II-items, factors and severities and showed both negative and positive correlations with HAMD-17 items. At T1 and within the controls, no such relationships were observed. At T0 and T1, levels of both pro- and anti-inflammatory cytokines were significantly higher in treatment responders (ΔHAMD-17T0-T1≥50%,n=15) compared to non-responders. When controlled for baseline BDI, differences between groups were only found significant for IL-2 at T0. The results suggest cytokines are not generally pro-depressive but rather relate to more specific regulation of symptoms and severities in MD. Together with the association between cytokines and treatment responder status, these data support cytokines as a promising but still controversial biomarker of depression.

Abstract 403: Identification of CHROME as a Competing Endogenous RNA that Regulates Cholesterol Homeostasis

The discovery of microRNAs (miRNA) targeting gene pathways involved in HDL and LDL metabolism illuminated the potent role of non-coding RNAs in the regulation of cholesterol homeostasis. Long non-coding RNAs (lncRNA) have also been identified as crucial regulators of gene expression; however, few have been fully characterized. Here we report a novel human lncRNA, CHROME (Cholesterol Homeostasis Regulator Of MicroRNA Expression), that functions as a competing endogenous RNA to regulate cellular cholesterol homeostasis. We show that CHROME has 7 broadly expressed variants that are transcriptionally regulated by the cholesterol-sensing liver X receptors. Computational analyses revealed that CHROME harbors binding sites for multiple (11) miRNAs involved in cholesterol homeostasis, including miR-27b and miR-33a/b, which function as hubs controlling the expression of genes involved in cholesterol efflux and HDL metabolism. Using CHROME knock-down and overexpression, we demonstrate that CHROME acts as a ‘miRNA sponge’ that sequesters these miRNAs, limiting their ability to repress target genes, including ABCA1, OSBPL6 and ANGPTL3. Consistent with this, we show that overexpression of CHROME increases cholesterol efflux, whereas its silencing reduces cholesterol efflux from primary human hepatocytes and macrophages. As hepatic cholesterol efflux via ABCA1 plays a central role in HDL biogenesis, we investigated the relationship of CHROME to its miRNA targets and plasma levels of HDL cholesterol in liver samples from a cohort of 200 healthy individuals. This analysis showed that CHROME is inversely correlated with miR-27b and miR-33a/b levels, and positively correlated with levels of their target genes and plasma HDL cholesterol. Collectively, these findings identify CHROME as a key regulatory component of the non-coding RNA circuitry that controls cellular cholesterol efflux and plasma HDL levels in humans.