CADASIL (cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy) is the most prevalent hereditary small vessel disease. CADASIL patients typically develop... Show moreCADASIL (cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy) is the most prevalent hereditary small vessel disease. CADASIL patients typically develop recurrent strokes from mid-adult age onwards, leading to cognitive impairment and ultimately vascular dementia. As there is currently no therapy that can delay or prevent CADASIL, the CADASIL research group of the Leiden University Medical Center is developing a therapeutic approach for CADASIL, called “NOTCH3 cysteine correction”.The aim of this PhD-project was to advance CADASIL therapy development.The work in this thesis provides the first in human evidence that the therapeutic approach of NOTCH3 cysteine correction leads to reduced protein aggregation, by describing a family with naturally occurring NOTCH3 cysteine correction. Furthermore, this thesis includes the results of the longest follow-up study to date of individuals with CADASIL, as well as and the identification of Neurofilament Light-chain (NfL) as blood biomarker in CADASIL. In a pre-clinical CADASIL disease model, potential pre-clinical biomarkers were explored and this resulted in the development of a GOM deposit classification system. Show less
Patients with Parkinson's Disease may be eligible for Deep Brain Stimulation (DBS) in case of severe motor complications. This thesis provides indications for improving patient selection for DBS,... Show morePatients with Parkinson's Disease may be eligible for Deep Brain Stimulation (DBS) in case of severe motor complications. This thesis provides indications for improving patient selection for DBS, as well as describing new biomarkers based on Electroencephalography (EEG) to aid during the DBS selection process. Show less
Serum biomarkers are an important tool in the baseline risk assessment and diagnosis of cardiovascular disease in cancer patients receiving cardiotoxic cancer treatments. Increases in cardiac... Show moreSerum biomarkers are an important tool in the baseline risk assessment and diagnosis of cardiovascular disease in cancer patients receiving cardiotoxic cancer treatments. Increases in cardiac biomarkers including cardiac troponin and natriuretic peptides can be used to guide initiation of cardioprotective treatments for cancer patients during treatment and to monitor the response to cardioprotective treatments, and they also offer prognostic value. This position statement examines the role of cardiac biomarkers in the management of cancer patients. The Cardio-Oncology Study Group of the Heart Failure Association (HFA) of the European Society of Cardiology (ESC) in collaboration with the Cardio-Oncology Council of the ESC have evaluated the current evidence for the role of cardiovascular biomarkers in cancer patients before, during and after cardiotoxic cancer therapies. The characteristics of the main two biomarkers troponin and natriuretic peptides are discussed, the link to the mechanisms of cardiovascular toxicity, and the evidence for their clinical use in surveillance during and after anthracycline chemotherapy, trastuzumab and HER2-targeted therapies, vascular endothelial growth factor inhibitors, proteasome inhibitors, immune checkpoint inhibitors, cyclophosphamide and radiotherapy. Novel surveillance clinical pathways integrating cardiac biomarkers for cancer patients receiving anthracycline chemotherapy or trastuzumab biomarkers are presented and future direction in cardio-oncology biomarker research is discussed. Show less
Background: Serum biomarkers may inform and improve care in traumatic brain injury (TBI). We aimed to correlate serum biomarkers with clinical severity, care path and imaging abnormalities in TBI,... Show moreBackground: Serum biomarkers may inform and improve care in traumatic brain injury (TBI). We aimed to correlate serum biomarkers with clinical severity, care path and imaging abnormalities in TBI, and explore their incremental value over clinical characteristics in predicting computed tomographic (CT) abnormalities.Methods: We analyzed six serum biomarkers (S100B, NSE, GFAP, UCH-L1, NFL and t-tau) obtained <24 h post-injury from 2867 patients with any severity of TBI in the Collaborative European NeuroTrauma Effectiveness Research (CENTER-TBI) Core Study, a prospective, multicenter, cohort study. Univariable and multivariable logistic regression analyses were performed. Discrimination was assessed by the area under the receiver operating characteristic curve (AUC) with 95% confidence intervals.Findings: All biomarkers scaled with clinical severity and care path (ER only, ward admission, or ICU), and with presence of CT abnormalities. GFAP achieved the highest discrimination for predicting CT abnormalities (AUC 0.89 [95%CI: 0.87-0.90]), with a 99% likelihood of better discriminating CT-positive patients than clinical characteristics used in contemporary decision rules. In patients with mild TBI, GFAP also showed incremental diagnostic value: discrimination increased from 0.84 [95%CI: 0.83-0.86] to 0.89 [95%CI: 0.87-0.90] when GFAP was included. Results were consistent across strata, and injury severity. Combinations of biomarkers did not improve discrimination compared to GFAP alone.Interpretation: Currently available biomarkers reflect injury severity, and serum GFAP, measured within 24 h after injury, outperforms clinical characteristics in predicting CT abnormalities. Our results support the further development of serum GFAP assays towards implementation in clinical practice, for which robust clinical assay platforms are required.(C) 2020 The Authors. Published by Elsevier B.V. Show less
There is a lack of reliable, repeatable, and non-invasive clinical endpoints when investigating treatments for intellectual disability (ID). The aim of this study is to explore a novel approach... Show moreThere is a lack of reliable, repeatable, and non-invasive clinical endpoints when investigating treatments for intellectual disability (ID). The aim of this study is to explore a novel approach towards developing new endpoints for neurodevelopmental disorders, in this case for ARID1B-related ID. In this study, twelve subjects with ARID1B-related ID and twelve age-matched controls were included in this observational case-control study. Subjects performed a battery of non-invasive neurobehavioral and neurophysiological assessments on two study days. Test domains included cognition, executive functioning, and eye tracking. Furthermore, several electrophysiological assessments were performed. Subjects wore a smartwatch (Withings (R) Steel HR) for 6 days. Tests were systematically assessed regarding tolerability, variability, repeatability, difference with control group, and correlation with traditional endpoints. Animal fluency, adaptive tracking, body sway, and smooth pursuit eye movements were assessed as fit-for-purpose regarding all criteria, while physical activity, heart rate, and sleep parameters show promise as well. The event-related potential waveform of the passive oddball and visual evoked potential tasks showed discriminatory ability, but EEG assessments were perceived as extremely burdensome. This approach successfully identified fit-for-purpose candidate endpoints for ARID1B-related ID and possibly for other neurodevelopmental disorders. Next, results could be replicated in different ID populations or the assessments could be included as exploratory endpoint in interventional trials in ARID1B-related ID. Show less
Introduction. Vulvar squamous cell carcinoma (VSCC) is a rare malignancy with an increasing incidence, especially in young women. Surgical treatment of VSCC is associated with significant morbidity... Show moreIntroduction. Vulvar squamous cell carcinoma (VSCC) is a rare malignancy with an increasing incidence, especially in young women. Surgical treatment of VSCC is associated with significant morbidity and high recurrence rates, which is related to the limited ability to distinguish (pre)malignant from healthy tissue. There is a need for new tools for specific real-time detection of occult tumor lesions and localization of cancer margins in patients with VSCC. Several tumor-specific imaging techniques are developed to recognize malignant tissue by targeting tumor markers. We present a systematic review to identify, evaluate, and summarize potential markers for tumor-specific imaging of VSCC.Methods. Relevant papers were identified by a systematic cross-database literature search developed with assistance of an experienced librarian. Data were extracted from eligible papers and reported based on the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines. VSCC-specific tumor markers were valued based on a weighted scoring system, in which each biomarker was granted points based on ranked eligibility criteria: I) percentage expression, II) sample size, and Ill) in vivo application.Results. In total 627 papers were included of which 22 articles met the eligibility criteria. Twelve VSCC-specific tumor markers were identified and of these 7 biomarkers were considered most promising: EGFR, CD44v6, GLUT1, MRP1, MUC1, CXCR-4 and VEGF-A.Discussion. This overview identified 7 potential biomarkers that can be used in the development of VSCCspecific tracers for real-time and precise localization of tumor tissue before, during, and after treatment. These biomarkers were identified in a small number of samples, without discriminating for VSCC-specific hallmarks such as HPV-status. Before clinical development, experimental studies should first aim at validation of these biomarkers using immunohistochemistry and cell line-based examination, discriminating for HPV-status and the expression rate in lymph nodes and precursor lesions. (C) 2019 Published by Elsevier Inc. Show less
BACKGROUND: Depression has been associated with metabolic alterations, which adversely impact cardiometabolic health. Here, a comprehensive set of metabolic markers, predominantly lipids, was... Show moreBACKGROUND: Depression has been associated with metabolic alterations, which adversely impact cardiometabolic health. Here, a comprehensive set of metabolic markers, predominantly lipids, was compared between depressed and nondepressed persons.METHODS: Nine Dutch cohorts were included, comprising 10,145 control subjects and 5283 persons with depression, established with diagnostic interviews or questionnaires. A proton nuclear magnetic resonance metabolomics platform provided 230 metabolite measures: 51 lipids, fatty acids, and low-molecular-weight metabolites; 98 lipid composition and particle concentration measures of lipoprotein subclasses; and 81 lipid and fatty acids ratios. For each metabolite measure, logistic regression analyses adjusted for gender, age, smoking, fasting status, and lipid-modifying medication were performed within cohort, followed by random-effects meta-analyses.RESULTS: Of the 51 lipids, fatty acids, and low-molecular-weight metabolites, 21 were significantly related to depression (false discovery rate q < .05). Higher levels of apolipoprotein B, very-low-density lipoprotein cholesterol, triglycerides, diglycerides, total and monounsaturated fatty acids, fatty acid chain length, glycoprotein acetyls, tyrosine, and isoleucine and lower levels of high-density lipoprotein cholesterol, acetate, and apolipoprotein Al were associated with increased odds of depression. Analyses of lipid composition indicators confirmed a shift toward less high-density lipoprotein and more very-low-density lipoprotein and triglyceride particles in depression. Associations appeared generally consistent across gender, age, and body mass index strata and across cohorts with depressive diagnoses versus symptoms.CONCLUSIONS: This large-scale meta-analysis indicates a clear distinctive profile of circulating lipid metabolites associated with depression, potentially opening new prevention or treatment avenues for depression and its associated cardiometabolic comorbidity. Show less
Harmonization of acquisition and analysis protocols is an important step in the validation of BOLD MRI as a renal biomarker. This harmonization initiative provides technical recommendations based... Show moreHarmonization of acquisition and analysis protocols is an important step in the validation of BOLD MRI as a renal biomarker. This harmonization initiative provides technical recommendations based on a consensus report with the aim to move towards standardized protocols that facilitate clinical translation and comparison of data across sites. We used a recently published systematic review paper, which included a detailed summary of renal BOLD MRI technical parameters and areas of investigation in its supplementary material, as the starting point in developing the survey questionnaires for seeking consensus. Survey data were collected via the Delphi consensus process from 24 researchers on renal BOLD MRI exam preparation, data acquisition, data analysis, and interpretation. Consensus was defined as >= 75% unanimity in response. Among 31 survey questions, 14 achieved consensus resolution, 12 showed clear respondent preference (65-74% agreement), and 5 showed equal (50/50%) split in opinion among respondents. Recommendations for subject preparation, data acquisition, processing and reporting are given based on the survey results and review of the literature. These technical recommendations are aimed towards increased inter-site harmonization, a first step towards standardization of renal BOLD MRI protocols across sites. We expect this to be an iterative process updated dynamically based on progress in the field. Show less
Potential relevant biomarkers can be found at different levels in tumour developmentand disease progression. This thesis is divided into three overarching parts. Colorectalcancer was studied from... Show morePotential relevant biomarkers can be found at different levels in tumour developmentand disease progression. This thesis is divided into three overarching parts. Colorectalcancer was studied from a population-based perspective (part I) to a molecular level,detailed as protein expression (part II) and (epi)genetics (part III), as indicated in Figure 2.In part I the use of adjuvant chemotherapy in patients with locally advanced rectalcancer, who underwent resection after preoperative (chemo)radiotherapy, wasevaluated in a meta-analysis based on individual patient data. Since four randomizedcontrolled trials individually did not end the ongoing debate about the role of adjuvantchemotherapy 14,68-70. In part II the ability by tumour cells to evade the immunerecognition was studied, especially the role of the non-classical HLA class I moleculeHLA-G was studied in detail. In part III, an epigenetic biomarker, LINE-1 methylationlevel, was studied in a dedicated stage II colon cohort. In addition, an establishedgenetic biomarker for colon cancer, MSI, was studied in a large rectal cancer cohort. Show less
Background Duchenne muscular dystrophy (DMD) is a fatal muscle-wasting disorder caused by genetic loss of dystrophin protein. Extracellular microRNAs (ex-miRNAs) are putative, minimally invasive... Show moreBackground Duchenne muscular dystrophy (DMD) is a fatal muscle-wasting disorder caused by genetic loss of dystrophin protein. Extracellular microRNAs (ex-miRNAs) are putative, minimally invasive biomarkers of DMD. Specific ex-miRNAs (e.g. miR-1, miR-133a, miR-206, and miR-483) are highly up-regulated in the serum of DMD patients and dystrophic animal models and are restored to wild-type levels following exon skipping-mediated dystrophin rescue in mdx mice. As such, ex-miRNAs are promising pharmacodynamic biomarkers of exon skipping efficacy. Here, we aimed to determine the degree to which ex-miRNA levels reflect the underlying level of dystrophin protein expression in dystrophic muscle. Methods Candidate ex-miRNA biomarker levels were investigated in mdx mice in which dystrophin was restored with peptide-PMO (PPMO) exon skipping conjugates and in mdx-Xist(Delta hs) mice that express variable amounts of dystrophin from birth as a consequence of skewed X-chromosome inactivation. miRNA profiling was performed in mdx-Xist(Delta hs) mice using the FirePlex methodology and key results validated by small RNA TaqMan RT-qPCR. The muscles from each animal model were further characterized by dystrophin Western blot and immunofluorescence staining. Results The restoration of ex-miRNA abundance observed following PPMO treatment was not recapitulated in the high dystrophin-expressing mdx-Xist(Delta hs) group, despite these animals expressing similar amounts of total dystrophin protein (similar to 37% of wild-type levels). Instead, ex-miRNAs were present at high levels in mdx-Xist(Delta hs) mice regardless of dystrophin expression. PPMO-treated muscles exhibited a uniform pattern of dystrophin localization and were devoid of regenerating fibres, whereas mdx-Xist(Delta hs) muscles showed non-homogeneous dystrophin staining and sporadic regenerating foci. Conclusions Uniform dystrophin expression is required to prevent ex-miRNA release, stabilize myofiber turnover, and attenuate pathology in dystrophic muscle. Show less
Spoel, E. van der; Vliet, N.A. van; Heemst, D. van 2019
Specific hallmarks are thought to underlie the ageing process and age-related functional decline. In this viewpoint, we put forward the hypothesis that disturbances in the process of tissue... Show moreSpecific hallmarks are thought to underlie the ageing process and age-related functional decline. In this viewpoint, we put forward the hypothesis that disturbances in the process of tissue maintenance are an important common denominator that may lie in between specific hallmarks of ageing (i.e. damage and responses to damage) and their ultimate (patho)physiological consequences (i.e. functional decline and age-related disease). As a first step towards verifying or falsifying this hypothesis, it will be important to measure biomarkers of tissue maintenance in future studies in different study populations. The main aim of the current paper is to discuss potential biomarkers of tissue maintenance that could be used in such future studies. Among the many tissues that could have been chosen to explore our hypothesis, to keep the paper manageable, we chose to focus on a selected number of tissues, namely bone, cartilage, muscle, and the brain, which are important for mobility and cognition and affected in several common age-related diseases, including osteoporosis, osteoarthritis, sarcopenia, and neurodegenerative diseases. Furthermore, we discuss the advantages and limitations of potential biomarkers for use in (pre)clinical studies. The proposed biomarkers should be validated in future research, for example by measuring these in humans with different rates of ageing. Show less
Matthijssen, X.M.E.; Wouters, F.; Boeters, D.M.; Boer, A.C.; Dakkak, Y.J.; Niemantsverdriet, E.; Helm-van Mil, A.H.M. van der 2019
Background: Diagnosing pneumonia can be challenging in general practice but is essential to distinguish from other respiratory tract infections because of treatment choice and outcome prediction.... Show moreBackground: Diagnosing pneumonia can be challenging in general practice but is essential to distinguish from other respiratory tract infections because of treatment choice and outcome prediction. We determined predictive signs, symptoms and biomarkers for the presence of pneumonia in patients with acute respiratory tract infection in primary care.Methods: From March 2012 until May 2016 we did a prospective observational cohort study in three radiology departments in the Leiden-The Hague area, The Netherlands. From adult patients we collected clinical characteristics and biomarkers, chest X ray results and outcome. To assess the predictive value of C-reactive protein (CRP), procalcitonin and midregional pro-adrenomedullin for pneumonia, univariate and multivariate binary logistic regression were used to determine risk factors and to develop a prediction model.Results: Two hundred forty-nine patients were included of whom 30 (12%) displayed a consolidation on chest X ray. Absence of runny nose and whether or not a patient felt ill were independent predictors for pneumonia. CRP predicts pneumonia better than the other biomarkers but adding CRP to the clinical model did not improve classification (- 4%); however, CRP helped guidance of the decision which patients should be given antibiotics.Conclusions: Adding CRP measurements to a clinical model in selected patients with an acute respiratory infection does not improve prediction of pneumonia, but does help in giving guidance on which patients to treat with antibiotics. Our findings put the use of biomarkers and chest X ray in diagnosing pneumonia and for treatment decisions into some perspective for general practitioners. Show less
Nauta, J.F.; Hummel, Y.M.; Tromp, J.; Ouwerkerk, W.; Meer, P. van der; Jin, X.Y.; ... ; Voors, A.A. 2019
Aims Heart failure is traditionally classified by left ventricular ejection fraction (LVEF), rather than by left ventricular (LV) geometry, with guideline-recommended therapies in heart failure... Show moreAims Heart failure is traditionally classified by left ventricular ejection fraction (LVEF), rather than by left ventricular (LV) geometry, with guideline-recommended therapies in heart failure with reduced ejection fraction (HFrEF) but not heart failure with preserved ejection fraction (HFpEF). Most patients with HFrEF have eccentric LV hypertrophy, but some have concentric LV hypertrophy. We aimed to compare clinical characteristics, biomarker patterns, and response to treatment of patients with HFrEF and eccentric vs. concentric LV hypertrophy. Methods and results We performed a retrospective post-hoc analysis including 1015 patients with HFrEF (LVEF <40%) from the multinational observational BIOSTAT-CHF study. LV geometry was classified using two-dimensional echocardiography. Network analysis of 92 biomarkers was used to investigate pathophysiologic pathways. Concentric LV hypertrophy was present in 142 (14%) patients, who were on average older and more likely hypertensive compared to those with eccentric LV hypertrophy. Network analysis revealed that N-terminal pro-B-type natriuretic peptide was an important hub in eccentric hypertrophy, whereas in concentric hypertrophy, tumour necrosis factor receptor 1, urokinase plasminogen activator surface receptor, paraoxonase and P-selectin were central hubs. Up-titration of beta-blockers was associated with a mortality benefit in HFrEF with eccentric but not concentric LV hypertrophy (P-value for interaction <= 0.001). For angiotensin-converting enzyme inhibitors/angiotensin receptor blockers, the hazard ratio for mortality was higher in concentric hypertrophy, but the interaction was not significant. Conclusion Patients with HFrEF with concentric hypertrophy have a clinical and biomarker phenotype that is distinctly different from those with eccentric hypertrophy. Patients with concentric hypertrophy may not experience similar benefit from up.-titration of angiotensin-converting enzyme inhibitors/angiotensin receptor blockers and beta-blockers compared to patients with eccentric hypertrophy. Show less
Messchendorp, A.L.; Meijer, E.; Visser, F.W.; Engels, G.E.; Kappert, P.; Losekoot, M.; ... ; DIPAK-1 Study Investigators 2019
Background: Markers currently used to predict the likelihood of rapid disease progression in patients with autosomal dominant polycystic kidney disease (ADPKD) are expensive and time consuming to... Show moreBackground: Markers currently used to predict the likelihood of rapid disease progression in patients with autosomal dominant polycystic kidney disease (ADPKD) are expensive and time consuming to assess and often have limited sensitivity. New, easy-to-measure markers are therefore needed that alone or in combination with conventional risk markers can predict the rate of disease progression. In the present study, we investigated the ability of tubular damage and inflammation markers to predict kidney function decline. Methods: At baseline, albumin, immunoglobulin G, kidney injury molecule 1, beta 2 microglobulin (beta 2MG), heart-type fatty acid-binding protein, neutrophil gelatinase-associated lipocalin, and monocyte chemotactic protein-1 -(MCP-1) were measured in 24-h urine samples of patients participating in a study investigating the therapeutic efficacy of lanreotide in ADPKD. Individual change in estimated glomerular filtration rate (eGFR) during follow-up was calculated using mixed-model analysis taking into account 13 -eGFRs (chronic kidney disease EPIdemiology) per patient. Logistic regression analysis was used to select urinary biomarkers that had the best association with rapidly progressive disease. The predictive value of these selected urinary biomarkers was compared to other risk scores using C-statistics. Results: Included were 302 patients of whom 53.3% were female, with an average age of 48 +/- 7 years, eGFR of 52 +/- 12 mL/min/1.73 m(2), and a height-adjusted total kidney volume (htTKV) of 1,082 (736-1,669) mL/m. At baseline, all urinary damage and inflammation markers were associated with baseline eGFR, also after adjustment for age, sex and baseline htTKV. For longitudinal analyses only patients randomized to standard care were considered (n = 152). A stepwise backward analysis revealed that beta 2MG and MCP-1 showed the strongest association with rapidly progressive disease. A urinary biomarker score was created by summing the ranking of tertiles of beta 2MG and MCP-1 excretion. The predictive value of this urinary biomarker score was higher compared to that of the Mayo htTKV classification (area under the curve [AUC] 0.73 [0.64-0.82] vs. 0.61 [0.51-0.71], p = 0.04) and comparable to that of the predicting renal outcomes in -ADPKD score (AUC 0.73 [0.64-0.82] vs. 0.65 [0.55-0.75], p = 0.18). In a second independent cohort with better kidney function, similar results were found for the urinary biomarker score. Conclusion: Measurement of urinary beta 2MG and MCP-1 excretion allows selection of ADPKD patients with rapidly progressive disease, with a predictive value comparable to or even higher than that of TKV or PKD mutation. Easy and inexpensive to measure urinary markers therefore hold promise to help predict prognosis in ADPKD. Show less
Boone, S.; Mook-Kanamori, D.; Rosendaal, F.; Heijer, M. den; Lamb, H.; Roos, A. de; ... ; Mutsert, R. de 2019
This thesis describes six clinical studies: two studies that investigate new compounds to treat symptoms of multiple sclerosis (MS) (chapters 2 and 3), one study that investigates a new... Show moreThis thesis describes six clinical studies: two studies that investigate new compounds to treat symptoms of multiple sclerosis (MS) (chapters 2 and 3), one study that investigates a new compound to treat MS (chapter 4) and three studies about the development of new methods to determine effects of a new class of compounds to treat MS (chapters 5, 6 and 7). Show less
Hooij, A. van; Eeden, S. van den; Richardus, R.; Fat, E.T.K.; Wilson, L.; Franken, K.L.M.C.; ... ; Geluk, A. 2019