95 results on '"Largiadèr CR"'
Search Results
2. Mutations upstream of fabI in triclosan resistant Staphylococcus aureus strains are associated with elevated fabI gene expression
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Ian Morrissey, Maria Laura Ciusa, Marco R. Oggioni, Stephen L. Leib, Leonardo Furi, Daniel R. Knight, Carlo R. Largiadèr, Lucilla Baldassarri, Denis Grandgirard, Grandgirard D, Furi L, Ciusa ML, Baldassarri L, Knight DR, Morrissey I, Largiadèr CR, Leib SL, and Oggioni MR
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Staphylococcus aureus ,Genotype ,Biocide ,Mutant ,Molecular Sequence Data ,Resistance ,Down-Regulation ,610 Medicine & health ,Biology ,Microarray ,medicine.disease_cause ,Microbiology ,Bacterial Proteins ,Gene expression ,Drug Resistance, Bacterial ,medicine ,Genetics ,Cross-resistance ,Promoter Regions, Genetic ,Gene ,Mutation ,Promoter mutation ,drug resistance ,Base Sequence ,Promoter ,fabI ,Enoyl-(Acyl-Carrier-Protein) Reductase (NADH) ,Triclosan ,Up-Regulation ,Gene expression profiling ,Anti-Infective Agents, Local ,570 Life sciences ,biology ,Biotechnology ,Research Article - Abstract
Background The enoyl-acyl carrier protein (ACP) reductase enzyme (FabI) is the target for a series of antimicrobial agents including novel compounds in clinical trial and the biocide triclosan. Mutations in fabI and heterodiploidy for fabI have been shown to confer resistance in S. aureus strains in a previous study. Here we further determined the fabI upstream sequence of a selection of these strains and the gene expression levels in strains with promoter region mutations. Results Mutations in the fabI promoter were found in 18% of triclosan resistant clinical isolates, regardless the previously identified molecular mechanism conferring resistance. Although not significant, a higher rate of promoter mutations were found in strains without previously described mechanisms of resistance. Some of the mutations identified in the clinical isolates were also detected in a series of laboratory mutants. Microarray analysis of selected laboratory mutants with fabI promoter region mutations, grown in the absence of triclosan, revealed increased fabI expression in three out of four tested strains. In two of these strains, only few genes other than fabI were upregulated. Consistently with these data, whole genome sequencing of in vitro selected mutants identified only few mutations except the upstream and coding regions of fabI, with the promoter mutation as the most probable cause of fabI overexpression. Importantly the gene expression profiling of clinical isolates containing similar mutations in the fabI promoter also showed, when compared to unrelated non-mutated isolates, a significant up-regulation of fabI. Conclusions In conclusion, we have demonstrated the presence of C34T, T109G, and A101C mutations in the fabI promoter region of strains with fabI up-regulation, both in clinical isolates and/or laboratory mutants. These data provide further observations linking mutations upstream fabI with up-regulated expression of the fabI gene. Electronic supplementary material The online version of this article (doi:10.1186/s12864-015-1544-y) contains supplementary material, which is available to authorized users.
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- 2015
3. Gender-Specific Prognostic Impact of Treosulfan Levels in High-Dose Chemotherapy for Multiple Myeloma.
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Heini AD, Kammermann K, Bacher U, Jeker B, Hayoz M, Aebi Y, Largiadèr CR, Nilius H, and Pabst T
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Introduction: The growing body of evidence around sexual and gender dimorphism in medicine, particularly in oncology, has highlighted differences in treatment response, outcomes, and side effects between males and females. Differences in drug metabolism, distribution, and elimination, influenced by factors like body composition and enzyme expression, contribute to these variations., Methods: We retrospectively analyzed data of 112 multiple myeloma (MM) patients treated with first-line high-dose chemotherapy (HDCT) with treosulfan and melphalan (TreoMel) followed by autologous stem cell transplantation (ASCT) at a single academic center between January 2020 and August 2022. We assessed response rate, progression-free survival (PFS), overall survival (OS), and toxicities in relation to gender and treosulfan exposure., Results: Our analysis revealed significant gender-specific differences in treosulfan exposure. Females had higher peak levels (343.8 vs. 309.0 mg/L, p = 0.0011) and area under the curve (AUC) (869.9 vs. 830.5 mg*h/L, p = 0.0427) compared to males. Higher treosulfan exposure was associated with increased mortality in females but not in males. Females with treosulfan AUC > 900 mg*h/L had significantly shorter overall survival, while PFS was unaffected by treosulfan exposure., Conclusion: Our study demonstrates that female patients undergoing TreoMel HDCT have higher treosulfan exposure than males and that females with higher levels are at increased risk for toxicity and adverse outcomes. These data suggest that higher treosulfan doses do not confer a benefit in terms of better outcomes for females. Therefore, exploring lower treosulfan doses for female MM patients undergoing TreoMel HDCT may be warranted to mitigate toxicity and improve outcomes.
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- 2024
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4. New diagnostic technologies in laboratory medicine: potential benefits and challenges.
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Nagler M, Nilius H, Michielin G, Masoodi M, and Largiadèr CR
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- Humans, Biosensing Techniques
- Abstract
Laboratory tests play a central role in medicine, as they help to make diagnoses, assess prognosis and risk of disease, and monitor therapies, thus contributing to 70% of all medical decisions. This cross‑sectional function offers great potential for technologic and organizational innovation to influence health care as a whole. In recent years, a variety of technologies have emerged and entered the field of medical research, or even medical care. A new generation of biosensors enables laboratory tests to be carried out at the point of care and allows for faster medical decisions. Modern devices allow for patient‑centric blood sampling, which eliminates the need for painful blood draws, patient traveling, and limits the workload of health care professionals. Analytical techniques, such as metabolomics, lipidomics, or proteomics can identify biomarkers extremely sensitively, even down to individual cells. Pharmacogenomics allows for determination of genetic polymorphisms that predict a response to chemotherapeutic agents. Machine‑learning approaches can handle large amounts of multilayered data for diagnostic applications. However, this enormous diagnostic potential is far from being utilized and only very few applications have been implemented in clinical practice. Why is this the case? In this article, we describe the key technologic fields, discuss their medical potential, and list obstacles to their implementation. In addition, we present a methodologic framework to support researchers, clinicians, and authorities in development and implementation of novel diagnostic approaches.
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- 2024
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5. Determinants of Interpatient Variability in Treosulfan Pharmacokinetics in AML Patients Undergoing Autologous Stem Cell Transplantation.
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Ayçiçek SG, Akhoundova D, Bacher U, Hayoz M, Aebi Y, Largiadèr CR, and Pabst T
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- Humans, Female, Male, Middle Aged, Adult, Aged, Retrospective Studies, Hematopoietic Stem Cell Transplantation methods, Antineoplastic Agents, Alkylating pharmacokinetics, Antineoplastic Agents, Alkylating therapeutic use, Busulfan analogs & derivatives, Busulfan pharmacokinetics, Busulfan therapeutic use, Leukemia, Myeloid, Acute therapy, Transplantation, Autologous
- Abstract
Limited data on treosulfan pharmacokinetics in adults, particularly regarding autologous stem cell transplantation (ASCT) in acute myeloid leukemia (AML), is available to date. Furthermore, correlations between treosulfan exposure, toxicity, and clinical outcome remain understudied. In this single-center retrospective study, we analyzed data from 55 AML patients who underwent HDCT with treosulfan (14 g/m
2 ) and melphalan (140 mg/m2 or 200 mg/m2 ) (TreoMel) between August 2019 and November 2023 at the University Hospital of Bern. We assessed treosulfan pharmacokinetics and correlations with several physiological parameters with potential impact on its interpatient variability. We further analyzed how treosulfan exposure correlates with toxicity and clinical outcomes. Women above 55 years showed higher area under the curve (AUC) levels (median: 946 mg*h/L, range: 776-1370 mg*h/L), as compared to women under 55 (median: 758 mg*h/L, range: 459-1214 mg*h/L, p = 0.0487). Additionally, women above 55 showed higher peak levels (median: 387 mg/L, range: 308-468 mg/L), as compared to men of the same age range (median: 326 mg/L, range: 264-395 mg/L, p = 0.0159). Treosulfan levels varied significantly with body temperature, liver enzymes, hemoglobin/hematocrit., and treosulfan exposure correlated with diarrhea severity in women over 55 ( p = 0.0076). Our study revealed age- and gender-related variability in treosulfan pharmacokinetics, with higher plasma levels observed in female patients above 55. Moreover, our data suggest that treosulfan plasma levels may vary with several physiological parameters and that higher treosulfan exposure may impact toxicity. Our study underlines the need for further research on treosulfan pharmacokinetics, especially in older patients undergoing HDCT in the ASCT setting.- Published
- 2024
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6. Approach for Phased Sequence-Based Genotyping of the Critical Pharmacogene Dihydropyrimidine Dehydrogenase ( DPYD ).
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Ambrodji A, Sadlon A, Amstutz U, Hoch D, Berger MD, Bastian S, Offer SM, and Largiadèr CR
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- Humans, Sequence Analysis, DNA methods, Neoplasms genetics, High-Throughput Nucleotide Sequencing methods, Polymorphism, Single Nucleotide, Alleles, Dihydrouracil Dehydrogenase (NADP) genetics, Genotype, Genotyping Techniques methods
- Abstract
Pre-treatment genotyping of four well-characterized toxicity risk-variants in the dihydropyrimidine dehydrogenase gene ( DPYD ) has been widely implemented in Europe to prevent serious adverse effects in cancer patients treated with fluoropyrimidines. Current genotyping practices are largely limited to selected commonly studied variants and are unable to determine phasing when more than one variant allele is detected. Recent evidence indicates that common DPYD variants modulate the functional impact of deleterious variants in a phase-dependent manner, where a cis - or a trans -configuration translates into different toxicity risks and dosing recommendations. DPYD is a large gene with 23 exons spanning nearly a mega-base of DNA, making it a challenging candidate for full-gene sequencing in the diagnostic setting. Herein, we present a time- and cost-efficient long-read sequencing approach for capturing the complete coding region of DPYD . We demonstrate that this method can reliably produce phased genotypes, overcoming a major limitation with current methods. This method was validated using 21 subjects, including two cancer patients, each of whom carried multiple DPYD variants. Genotype assignments showed complete concordance with conventional approaches. Furthermore, we demonstrate that the method is robust to technical challenges inherent in long-range sequencing of PCR products, including reference alignment bias and PCR chimerism.
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- 2024
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7. Safety and Efficacy of High-Dose Chemotherapy with TreoMel 200 vs. TreoMel 140 in Acute Myeloid Leukemia Patients Undergoing Autologous Stem Cell Transplantation.
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Eggimann M, Akhoundova D, Nilius H, Hoffmann M, Hayoz M, Aebi Y, Largiadèr CR, Daskalakis M, Bacher U, and Pabst T
- Abstract
(1) Background: Treosulfan and melphalan (TreoMel)-based high-dose chemotherapy (HDCT) has shown promising safety and efficacy as a conditioning regimen for acute myeloid leukemia (AML) patients undergoing autologous stem cell transplantation (ASCT). However, despite intensive first-line induction treatment and upfront consolidation with HDCT and ASCT, AML relapse rates are still high, and further efforts are needed to improve patient outcomes. The aim of this study was to compare two melphalan dose schedules in regard to the safety of TreoMel HDCT and patient outcomes. (2) Methods: We retrospectively analyzed the safety and efficacy of two melphalan dose schedules combined with standard-dose treosulfan in AML patients undergoing HDCT and ASCT at the University Hospital of Bern, Switzerland, between August 2019 and August 2023. Patients received treosulfan 42 g/m
2 combined with either melphalan 140 mg/m2 (TreoMel 140) or melphalan 200 mg/m2 (TreoMel 200). Co-primary endpoints were progression-free survival (PFS), overall survival (OS), as well as safety profile. (3) Results: We included a total of 51 AML patients: 31 (60.8%) received TreoMel 140 and 20 (39.2%) TreoMel 200. The patients' basal characteristics were comparable between both cohorts. No significant differences in the duration of hospitalization or the adverse event profile were identified. There were no statistically significant differences in relapse (0.45 vs. 0.30, p = 0.381) and mortality rates (0.42 vs. 0.15, p = 0.064) between the melphalan 140 mg/m2 and 200 mg/m2 cohorts, nor for PFS (HR: 0.81, 95% CI: 0.29-2.28, p = 0.70) or OS (HR: 0.70, 95% CI: 0.19-2.57, p = 0.59) for the TreoMel 140 vs. TreoMel 200 cohort. (4) Conclusions: A higher dose of melphalan (TreoMel 200) was well tolerated overall. No statistically significant differences for patient outcomes could be observed, possibly due to the relatively small patient cohort and the short follow-up. A longer follow-up and prospective randomized studies would be required to confirm the safety profile and clinical benefit.- Published
- 2024
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8. The gut microbiome and HLA-B27-associated anterior uveitis: a case-control study.
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Morandi SC, Herzog EL, Munk M, Kreuzer M, Largiadèr CR, Wolf S, Zinkernagel M, and Zysset-Burri DC
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- Humans, Female, Male, Middle Aged, Adult, Case-Control Studies, Aged, HLA-B27 Antigen genetics, HLA-B27 Antigen immunology, Gastrointestinal Microbiome physiology, Uveitis, Anterior microbiology, Uveitis, Anterior immunology
- Abstract
Background: The human gut microbiome (GM) is involved in inflammation and immune response regulation. Dysbiosis, an imbalance in this ecosystem, facilitates pathogenic invasion, disrupts immune equilibrium, and potentially triggers diseases including various human leucocyte antigen (HLA)-B27-associated autoinflammatory and autoimmune diseases such as inflammatory bowel disease (IBD) and spondyloarthropathy (SpA). This study assesses compositional and functional alterations of the GM in patients with HLA-B27-associated non-infectious anterior uveitis (AU) compared to healthy controls., Methods: The gut metagenomes of 20 patients with HLA-B27-associated non-infectious AU, 21 age- and sex-matched HLA-B27-negative controls, and 6 HLA-B27-positive healthy controls without a history of AU were sequenced using the Illumina NovaSeq 6000 platform for whole metagenome shotgun sequencing. To identify taxonomic and functional features with significantly different relative abundances between groups and to identify associations with clinical metadata, the multivariate association by linear models (MaAsLin) R package was applied., Results: Significantly higher levels of the Eubacterium ramulus species were found in HLA-B27-negative controls (p = 0.0085, Mann-Whitney U-test). No significant differences in microbial composition were observed at all other taxonomic levels. Functionally, the lipid IV
A biosynthesis pathway was upregulated in patients (p < 0.0001, Mann-Whitney U-test). A subgroup analysis comparing patients with an active non-infectious AU to their age- and sex-matched HLA-B27-negative controls, showed an increase of the species Phocaeicola vulgatus in active AU (p = 0.0530, Mann-Whitney U-test). An additional analysis comparing AU patients to age- and sex-matched HLA-B27-positive controls, showed an increase of the species Bacteroides caccae in controls (p = 0.0022, Mann-Whitney U-test)., Conclusion: In our cohort, non-infectious AU development is associated with compositional and functional alterations of the GM. Further research is needed to assess the causality of these associations, offering potentially novel therapeutic strategies., (© 2024. The Author(s).)- Published
- 2024
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9. Increased erythroferrone levels in malarial anaemia.
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Neyer PJ, Kaboré B, Nakas CT, Diallo S, Tinto H, Post A, van der Ven AJ, Huber AR, Largiadèr CR, and Hammerer-Lercher A
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- Animals, Female, Humans, Male, Mice, Anemia blood, Anemia etiology, Anemia, Iron-Deficiency blood, Hepcidins blood, Iron blood, Iron metabolism, Biomarkers blood, Malaria complications, Malaria blood, Peptide Hormones blood
- Abstract
We assessed the diagnostic potential of erythroferrone as a biomarker for iron homeostasis comparing iron deficiency cases with anaemia of inflammation and controls. The dysregulation of the hepcidin axis was observed by Latour et al. in a mouse model of malarial anaemia induced by prolonged Plasmodium infection leading to increased erythroferrone concentrations. In line with that, we found significantly higher erythroferrone levels in cases with malaria and anaemia in an African population, compared to asymptomatic controls. Therefore, our findings extend the previous ones of the mouse model, suggesting also a dysregulation of the hepcidin axis in humans, which should be further corroborated in prospective studies and may lay the basis for the development of improved treatment strategies according to ERFE concentrations in such patients., (© 2024 The Authors. British Journal of Haematology published by British Society for Haematology and John Wiley & Sons Ltd.)
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- 2024
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10. Germline cis variant determines epigenetic regulation of the anti-cancer drug metabolism gene dihydropyrimidine dehydrogenase ( DPYD ).
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Zhang T, Ambrodji A, Huang H, Bouchonville KJ, Etheridge AS, Schmidt RE, Bembenek BM, Temesgen ZB, Wang Z, Innocenti F, Stroka D, Diasio RB, Largiadèr CR, and Offer SM
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- Humans, Antimetabolites, Antineoplastic pharmacology, Antimetabolites, Antineoplastic metabolism, Antineoplastic Agents pharmacology, Cell Line, Tumor, Germ-Line Mutation, Dihydrouracil Dehydrogenase (NADP) genetics, Dihydrouracil Dehydrogenase (NADP) metabolism, Enhancer Elements, Genetic, Epigenesis, Genetic, Fluorouracil pharmacology, Fluorouracil metabolism
- Abstract
Enhancers are critical for regulating tissue-specific gene expression, and genetic variants within enhancer regions have been suggested to contribute to various cancer-related processes, including therapeutic resistance. However, the precise mechanisms remain elusive. Using a well-defined drug-gene pair, we identified an enhancer region for dihydropyrimidine dehydrogenase (DPD, DPYD gene) expression that is relevant to the metabolism of the anti-cancer drug 5-fluorouracil (5-FU). Using reporter systems, CRISPR genome-edited cell models, and human liver specimens, we demonstrated in vitro and vivo that genotype status for the common germline variant (rs4294451; 27% global minor allele frequency) located within this novel enhancer controls DPYD transcription and alters resistance to 5-FU. The variant genotype increases recruitment of the transcription factor CEBPB to the enhancer and alters the level of direct interactions between the enhancer and DPYD promoter. Our data provide insight into the regulatory mechanisms controlling sensitivity and resistance to 5-FU., Competing Interests: TZ, AA, HH, KB, AE, RS, BB, ZT, ZW, DS, RD, CL No competing interests declared, FI Currently an AbbVie employee and receives stocks from the company, SO Reports current research support from Processa Pharmaceuticals, Inc, which are outside of the conduct of this study. Has previously served as an independent consultant for Processa Pharmaceuticals, Inc, in matters not related to this study, (© 2024, Zhang et al.)
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- 2024
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11. Dihydropyrimidine dehydrogenase gene variants for predicting grade 4-5 fluoropyrimidine-induced toxicity: FUSAFE individual patient data meta-analysis.
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Le Teuff G, Cozic N, Boyer JC, Boige V, Diasio RB, Taieb J, Meulendijks D, Palles C, Schwab M, Deenen M, Largiadèr CR, Marinaki A, Jennings BA, Wettergren Y, Di Paolo A, Gross E, Budai B, Ackland SP, van Kuilenburg ABP, McLeod HL, Milano G, Thomas F, Loriot MA, Kerr D, Schellens JHM, Laurent-Puig P, Shi Q, Pignon JP, and Etienne-Grimaldi MC
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- Humans, Fluorouracil adverse effects, Dihydrouracil Dehydrogenase (NADP) genetics, Heterozygote, Genotype, Capecitabine adverse effects, Antineoplastic Agents, Dihydropyrimidine Dehydrogenase Deficiency
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Background: Dihydropyrimidine dehydrogenase (DPD) deficiency is the main known cause of life-threatening fluoropyrimidine (FP)-induced toxicities. We conducted a meta-analysis on individual patient data to assess the contribution of deleterious DPYD variants *2A/D949V/*13/HapB3 (recommended by EMA) and clinical factors, for predicting G4-5 toxicity., Methods: Study eligibility criteria included recruitment of Caucasian patients without DPD-based FP-dose adjustment. Main endpoint was 12-week haematological or digestive G4-5 toxicity. The value of DPYD variants *2A/p.D949V/*13 merged, HapB3, and MIR27A rs895819 was evaluated using multivariable logistic models (AUC)., Results: Among 25 eligible studies, complete clinical variables and primary endpoint were available in 15 studies (8733 patients). Twelve-week G4-5 toxicity prevalence was 7.3% (641 events). The clinical model included age, sex, body mass index, schedule of FP-administration, concomitant anticancer drugs. Adding *2A/p.D949V/*13 variants (at least one allele, prevalence 2.2%, OR 9.5 [95%CI 6.7-13.5]) significantly improved the model (p < 0.0001). The addition of HapB3 (prevalence 4.0%, 98.6% heterozygous), in spite of significant association with toxicity (OR 1.8 [95%CI 1.2-2.7]), did not improve the model. MIR27A rs895819 was not associated with toxicity, irrespective of DPYD variants., Conclusions: FUSAFE meta-analysis highlights the major relevance of DPYD *2A/p.D949V/*13 combined with clinical variables to identify patients at risk of very severe FP-related toxicity., (© 2024. The Author(s), under exclusive licence to Springer Nature Limited.)
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- 2024
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12. Exploring the host factors affecting asymptomatic Plasmodium falciparum infection: insights from a rural Burkina Faso study.
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Neyer PJ, Kaboré B, Nakas CT, Hartmann B, Post A, Diallo S, Tinto H, Hammerer-Lercher A, Largiadèr CR, van der Ven AJ, and Huber AR
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- Adolescent, Child, Humans, Burkina Faso epidemiology, Plasmodium falciparum genetics, Hemoglobin, Sickle, Asymptomatic Infections epidemiology, Hepcidins, Malaria, Falciparum epidemiology
- Abstract
Background: Asymptomatic Plasmodium falciparum parasitaemia forms a reservoir for the transmission of malaria disease in West Africa. Certain haemoglobin variants are known to protect against severe malaria infection. However, data on the potential roles of haemoglobin variants and nongenetic factors in asymptomatic malaria infection is scarce and controversial. Therefore, this study investigated the associations of iron homeostasis, inflammation, nutrition, and haemoglobin mutations with parasitaemia in an asymptomatic cohort from a P. falciparum-endemic region during the high transmission season., Methods: A sub-study population of 688 asymptomatic individuals (predominantly children and adolescents under 15 years, n = 516) from rural Burkina Faso previously recruited by the NOVAC trial (NCT03176719) between June and October 2017 was analysed. Parasitaemia was quantified with conventional haemocytometry. The haemoglobin genotype was determined by reverse hybridization assays targeting a selection of 21 HBA and 22 HBB mutations. Demographics, inflammatory markers (interleukins 6 and 10, hepcidin), nutritional status (mid upper-arm circumference and body mass index), and anaemia (total haemoglobin, ferritin, soluble transferrin receptor) were assessed as potential predictors through logistic regression., Results: Malaria parasites were detected in 56% of subjects. Parasitaemia was associated most strongly with malnutrition. The effect size increased with malnutrition severity (OR = 6.26, CI
95 : 2.45-19.4, p < 0.001). Furthermore, statistically significant associations (p < 0.05) with age, cytokines, hepcidin and heterozygous haemoglobin S were observed., Conclusions: According to these findings, asymptomatic parasitaemia is attenuated by haemoglobin S, but not by any of the other detected genotypes. Aside from evidence for slight iron imbalance, overall undernutrition was found to predict parasitaemia; thus, further investigations are required to elucidate causality and inform strategies for interventions., (© 2023. BioMed Central Ltd., part of Springer Nature.)- Published
- 2023
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13. Investigation of Different Library Preparation and Tissue of Origin Deconvolution Methods for Urine and Plasma cfDNA Methylome Analysis.
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Kueng N, Sidler D, Banz V, Largiadèr CR, Ng CKY, and Amstutz U
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Methylation sequencing is a promising approach to infer the tissue of origin of cell-free DNA (cfDNA). In this study, a single- and a double-stranded library preparation approach were evaluated with respect to their technical biases when applied on cfDNA from plasma and urine. Additionally, tissue of origin (TOO) proportions were evaluated using two deconvolution methods. Sequencing cfDNA from urine using the double-stranded method resulted in a substantial within-read methylation bias and a lower global methylation (56.0% vs. 75.8%, p ≤ 0.0001) compared to plasma cfDNA, both of which were not observed with the single-stranded approach. Individual CpG site-based TOO deconvolution resulted in a significantly increased proportion of undetermined TOO with the double-stranded method (urine: 32.3% vs. 1.9%; plasma: 5.9% vs. 0.04%; p ≤ 0.0001), but no major differences in proportions of individual cell types. In contrast, fragment-level deconvolution led to multiple cell types, with significantly different TOO proportions between the two methods. This study thus outlines potential limitations of double-stranded library preparation for methylation analysis of cfDNA especially for urinary cfDNA. While the double-stranded method allows jagged end analysis in addition to TOO analysis, it leads to significant methylation bias in urinary cfDNA, which single-stranded methods can overcome.
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- 2023
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14. Efficacy and Safety of High-Dose Chemotherapy with Treosulfan and Melphalan in Multiple Myeloma.
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Gillich C, Akhoundova D, Hayoz M, Aebi Y, Largiadèr CR, Seipel K, Daskalakis M, Bacher U, and Pabst T
- Abstract
(1) Background: Upfront treatment consolidation with high-dose chemotherapy (HDCT) and autologous stem cell transplantation (ASCT) has relevantly contributed to achieving durable remissions following induction treatment in multiple myeloma (MM) patients. The optimization of HDCT regimens can, therefore, essentially contribute to improving the depth and duration of tumor remissions. To date, melphalan at 200 mg/m
2 is the standard HDCT regimen for fit MM patients. In our previous work, we showed promising efficacy and safety results for treosulfan (14 g/m2 ) and melphalan (200 mg/m2 ) (TreoMel) in acute myeloid leukemia (AML) patients receiving ASCT. Based on these data, TreoMel became the standard of care for fit MM patients at our institution. (2) Methods: We identified 115 consecutive MM patients who underwent consolidation with TreoMel between 01/2020 and 08/2022 at the University Hospital of Bern. We analyzed the safety and efficacy data, as well as the treosulfan pharmacokinetics, correlating them with tumor responses. (3) Results: A complete response (CR) rate of 84% was achieved, which is comparable to the CR rate reported for the quadruplet combination. The median PFS was 30 months (95% CI: 20.4-not reached), and the 31-month OS rate was 83%. The median area under the curve (AUC) for treosulfan was 952.5 mg*h/L (range: 527.4-1781.4), and the median peak level was 332.3 mg/L (range: 168-554). The treosulfan pharmacokinetics showed no significant correlation with MM responses after HDCT and ASCT. However, female patients had a significantly higher AUC ( p = 0.007) and peak value ( p = 0.001), and the higher values were associated with longer hospitalizations. (4) Conclusions: Treatment consolidation with TreoMel HDCT demonstrated a promising efficacy and safety profile in our cohort of MM patients and deserves further investigation in prospective studies.- Published
- 2023
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15. Implementation of dihydropyrimidine dehydrogenase deficiency testing in Europe.
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de With M, Sadlon A, Cecchin E, Haufroid V, Thomas F, Joerger M, van Schaik RHN, Mathijssen RHJ, and Largiadèr CR
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- Humans, Fluorouracil therapeutic use, Antimetabolites, Antineoplastic therapeutic use, Retrospective Studies, Dihydrouracil Dehydrogenase (NADP) genetics, Europe, Dihydropyrimidine Dehydrogenase Deficiency diagnosis, Dihydropyrimidine Dehydrogenase Deficiency genetics, Dihydropyrimidine Dehydrogenase Deficiency drug therapy
- Abstract
Background: The main cause for fluoropyrimidine-related toxicity is deficiency of the metabolizing enzyme dihydropyrimidine dehydrogenase (DPD). In 2020, the European Medicines Agency (EMA) recommended two methods for pre-treatment DPD deficiency testing in clinical practice: phenotyping using endogenous uracil concentration or genotyping for DPYD risk variant alleles. This study assessed the DPD testing implementation status in Europe before (2019) and after (2021) the release of the EMA recommendations., Methods: The survey was conducted from 16 March 2022 to 31 July 2022. An electronic form with seven closed and three open questions was e-mailed to 251 professionals with DPD testing expertise of 34 European countries. A descriptive analysis was conducted., Results: We received 79 responses (31%) from 23 countries. Following publication of the EMA recommendations, 87% and 75% of the countries reported an increase in the amount of genotype and phenotype testing, respectively. Implementation of novel local guidelines was reported by 21 responders (27%). Countries reporting reimbursement of both tests increased in 2021, and only four (18%) countries reported no coverage for any testing type. In 2019, major implementation drivers were 'retrospective assessment of fluoropyrimidine-related toxicity' (39%), and in 2021, testing was driven by 'publication of guidelines' (40%). Although the major hurdles remained the same after EMA recommendations-'lack of reimbursement' (26%; 2019 versus 15%; 2021) and 'lack of recognizing the clinical relevance by medical oncologists' (25%; 2019 versus 8%; 2021)-the percentage of specialists citing these decreased. Following EMA recommendations, 25% of responders reported no hurdles at all in the adoption of the new testing practice in the clinics., Conclusions: The EMA recommendations have supported the implementation of DPD deficiency testing in Europe. Key factors for successful implementation were test reimbursement and clear clinical guidelines. Further efforts to improve the oncologists' awareness of the clinical relevance of DPD testing in clinical practice are needed., Competing Interests: Disclosure The authors have declared no conflicts of interest. Data sharing Individual participant data collected by the survey, after de-identification, may be provided by the corresponding author on reasonable request to researchers who provide a methodologically sound proposal for the purpose of e.g. meta-analysis, with the permission of the co-authors., (Copyright © 2023 The Author(s). Published by Elsevier Ltd.. All rights reserved.)
- Published
- 2023
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16. Comparison of methods for donor-derived cell-free DNA quantification in plasma and urine from solid organ transplant recipients.
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Kueng N, Arcioni S, Sandberg F, Kuhn C, Banz V, Largiadèr CR, Sidler D, and Amstutz U
- Abstract
In allograft monitoring of solid organ transplant recipients, liquid biopsy has emerged as a novel approach using quantification of donor-derived cell-free DNA (dd-cfDNA) in plasma. Despite early clinical implementation and analytical validation of techniques, direct comparisons of dd-cfDNA quantification methods are lacking. Furthermore, data on dd-cfDNA in urine is scarce and high-throughput sequencing-based methods so far have not leveraged unique molecular identifiers (UMIs) for absolute dd-cfDNA quantification. Different dd-cfDNA quantification approaches were compared in urine and plasma of kidney and liver recipients: A) Droplet digital PCR (ddPCR) using allele-specific detection of seven common HLA-DRB1 alleles and the Y chromosome; B) high-throughput sequencing (HTS) using a custom QIAseq DNA panel targeting 121 common polymorphisms; and C) a commercial dd-cfDNA quantification method (AlloSeq
® cfDNA, CareDx). Dd-cfDNA was quantified as %dd-cfDNA, and for ddPCR and HTS using UMIs additionally as donor copies. In addition, relative and absolute dd-cfDNA levels in urine and plasma were compared in clinically stable recipients. The HTS method presented here showed a strong correlation of the %dd-cfDNA with ddPCR ( R2 = 0.98) and AlloSeq® cfDNA ( R2 = 0.99) displaying only minimal to no proportional bias. Absolute dd-cfDNA copies also correlated strongly ( τ = 0.78) between HTS with UMI and ddPCR albeit with substantial proportional bias (slope: 0.25; 95%-CI: 0.19-0.26). Among 30 stable kidney transplant recipients, the median %dd-cfDNA in urine was 39.5% (interquartile range, IQR: 21.8-58.5%) with 36.6 copies/μmol urinary creatinine (IQR: 18.4-109) and 0.19% (IQR: 0.01-0.43%) with 5.0 copies/ml (IQR: 1.8-12.9) in plasma without any correlation between body fluids. The median %dd-cfDNA in plasma from eight stable liver recipients was 2.2% (IQR: 0.72-4.1%) with 120 copies/ml (IQR: 85.0-138) while the median dd-cfDNA copies/ml was below 0.1 in urine. This first head-to-head comparison of methods for absolute and relative quantification of dd-cfDNA in urine and plasma supports a method-independent %dd-cfDNA cutoff and indicates the suitability of the presented HTS method for absolute dd-cfDNA quantification using UMIs. To evaluate the utility of dd-cfDNA in urine for allograft surveillance, absolute levels instead of relative amounts will most likely be required given the extensive variability of %dd-cfDNA in stable kidney recipients., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Kueng, Arcioni, Sandberg, Kuhn, Banz, Largiadèr, Sidler and Amstutz.)- Published
- 2023
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17. Population pharmacokinetic analyses of regorafenib and capecitabine in patients with locally advanced rectal cancer (SAKK 41/16 RECAP).
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Schmulenson E, Bovet C, Theurillat R, Decosterd LA, Largiadèr CR, Prost JC, Csajka C, Bärtschi D, Guckenberger M, von Moos R, Bastian S, Joerger M, and Jaehde U
- Subjects
- Humans, Antineoplastic Combined Chemotherapy Protocols therapeutic use, Capecitabine, Fluorouracil therapeutic use, Pyridines, Phenylurea Compounds, Rectal Neoplasms drug therapy, Rectal Neoplasms chemically induced
- Abstract
Aims: Locally advanced rectal cancer (LARC) is an area of unmet medical need with one third of patients dying from their disease. With response to neoadjuvant chemo-radiotherapy being a major prognostic factor, trial SAKK 41/16 assessed potential benefits of adding regorafenib to capecitabine-amplified neoadjuvant radiotherapy in LARC patients., Methods: Patients received regorafenib at three dose levels (40/80/120 mg once daily) combined with capecitabine 825 mg/m
2 bidaily and local radiotherapy. We developed population pharmacokinetic models from plasma concentrations of capecitabine and its metabolites 5'-deoxy-5-fluorocytidine and 5'-deoxy-5-fluorouridine as well as regorafenib and its metabolites M-2 and M-5 as implemented into SAKK 41/16 to assess potential drug-drug interactions (DDI). After establishing parent-metabolite base models, drug exposure parameters were tested as covariates within the respective models to investigate for potential DDI. Simulation analyses were conducted to quantify their impact., Results: Plasma concentrations of capecitabine, regorafenib and metabolites were characterized by one and two compartment models and absorption was described by parallel first- and zero-order processes and transit compartments, respectively. Apparent capecitabine clearance was 286 L/h (relative standard error [RSE] 14.9%, interindividual variability [IIV] 40.1%) and was reduced by regorafenib cumulative area under the plasma concentration curve (median reduction of 45.6%) as exponential covariate (estimate -4.10 × 10-4 , RSE 17.8%). Apparent regorafenib clearance was 1.94 L/h (RSE 12.1%, IIV 38.1%). Simulation analyses revealed significantly negative associations between capecitabine clearance and regorafenib exposure., Conclusions: This work informs the clinical development of regorafenib and capecitabine combination treatment and underlines the importance of studying potential DDI with new anticancer drug combinations., (© 2022 The Authors. British Journal of Clinical Pharmacology published by John Wiley & Sons Ltd on behalf of British Pharmacological Society.)- Published
- 2022
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18. Serological testing for SARS-CoV-2 antibodies in clinical practice: A comparative diagnostic accuracy study.
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Horn MP, Jonsdottir HR, Brigger D, Damonti L, Suter-Riniker F, Endrich O, Froehlich TK, Fiedler M, Largiadèr CR, Marschall J, Weber B, Eggel A, and Nagler M
- Subjects
- Antibodies, Neutralizing, Antibodies, Viral, COVID-19 Testing, Humans, Sensitivity and Specificity, COVID-19 diagnosis, SARS-CoV-2
- Abstract
Background: Serological tests are a powerful tool in the monitoring of infectious diseases and the detection of host immunity. However, manufacturers often provide diagnostic accuracy data generated through biased studies, and the performance in clinical practice is essentially unclear., Objectives: We aimed to determine the diagnostic accuracy of various serological testing strategies for (a) identification of patients with previous coronavirus disease-2019 (COVID-19) and (b) prediction of neutralizing antibodies against SARS-CoV-2 in real-life clinical settings., Methods: We prospectively included 2573 consecutive health-care workers and 1085 inpatients with suspected or possible previous COVID-19 at a Swiss University Hospital. Various serological immunoassays based on different analytical techniques (enzyme-linked immunosorbent assays, ELISA; chemiluminescence immunoassay, CLIA; electrochemiluminescence immunoassay, ECLIA; and lateral flow immunoassay, LFI), epitopes of SARS-CoV-2 (nucleocapsid, N; receptor-binding domain, RBD; extended RBD, RBD+; S1 or S2 domain of the spike [S] protein, S1/S2), and antibody subtypes (IgG, pan-Ig) were conducted. A positive real-time PCR test from a nasopharyngeal swab was defined as previous COVID-19. Neutralization assays with live SARS-CoV-2 were performed in a subgroup of patients to assess neutralization activity (n = 201)., Results: The sensitivity to detect patients with previous COVID-19 was ≥85% in anti-N ECLIA (86.8%) and anti-S1 ELISA (86.2%). Sensitivity was 84.7% in anti-S1/S2 CLIA, 84.0% in anti-RBD+LFI, 81.0% in anti-N CLIA, 79.2% in anti-RBD ELISA, and 65.6% in anti-N ELISA. The specificity was 98.4% in anti-N ECLIA, 98.3% in anti-N CLIA, 98.2% in anti-S1 ELISA, 97.7% in anti-N ELISA, 97.6% in anti-S1/S2 CLIA, 97.2% in anti-RBD ELISA, and 96.1% in anti-RBD+LFI. The sensitivity to detect neutralizing antibodies was ≥85% in anti-S1 ELISA (92.7%), anti-N ECLIA (91.7%), anti-S1/S2 CLIA (90.3%), anti-RBD+LFI (87.9%), and anti-RBD ELISA (85.8%). Sensitivity was 84.1% in anti-N CLIA and 66.2% in anti-N ELISA. The specificity was ≥97% in anti-N CLIA (100%), anti-S1/S2 CLIA (97.7%), and anti-RBD+LFI (97.9%). Specificity was 95.9% in anti-RBD ELISA, 93.0% in anti-N ECLIA, 92% in anti-S1 ELISA, and 65.3% in anti-N ELISA. Diagnostic accuracy measures were consistent among subgroups., Conclusions: The diagnostic accuracy of serological tests for SARS-CoV-2 antibodies varied remarkably in clinical practice, and the sensitivity to identify patients with previous COVID-19 deviated substantially from the manufacturer's specifications. The data presented here should be considered when using such tests to estimate the infection burden within a specific population and determine the likelihood of protection against re-infection., (© 2022 The Authors. Allergy published by European Academy of Allergy and Clinical Immunology and John Wiley & Sons Ltd.)
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- 2022
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19. Clinical Implementation of DPYD Pharmacogenetic Testing to Prevent Early-Onset Fluoropyrimidine-Related Toxicity in Cancer Patients in Switzerland.
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Begré UBM, Jörger M, Aebi S, Amstutz U, and Largiadèr CR
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The implementation of pharmacogenetic testing into clinical practice has been a slow process so far. Here, we review the implementation of pre-treatment testing of dihydropyrimidine dehydrogenase gene ( DPYD ) risk variants to prevent early-onset fluoropyrimidine (FP)-related toxicity in cancer patients in Switzerland based on data of a large Swiss diagnostic center. In January 2017, the Swiss Federal Office of Public Health introduced the reimbursement of DPYD testing by the compulsory health insurance in Switzerland based on evidence for the clinical relevance of DPYD -risk variants and the cost-effectiveness of pre-treatment testing, and on the availability of international guidelines. However, we did not observe a strong increase in DPYD testing at our diagnostic center from 2017 to 2019. Only a low number of DPYD -testing requests (28-42 per year), concerning mostly retrospective investigations of suspected FP-toxicity, were received. In contrast, we observed a 14-fold increase in DPYD testing together with a strong shift from retrospective to pre-treatment test requests upon the release of recommendations for DPYD testing prior to FP-treatment in April 2020 by the European Medicines Agency. This increase was mainly driven by three geographic regions of Switzerland, where partner institutions of previous research collaborations regarding FP-related toxicity are located and who acted as early-adopting institutions of DPYD testing. Our data suggest the important role of early adopters as accelerators of clinical implementation of pharmacogenetic testing by introducing these policies to their working environment and educating health workers from their own and nearby institutions., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Begré, Jörger, Aebi, Amstutz and Largiadèr.)
- Published
- 2022
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20. Comparison of Melphalan Combined with Treosulfan or Busulfan as High-Dose Chemotherapy before Autologous Stem Cell Transplantation in AML.
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Gurevich E, Hayoz M, Aebi Y, Largiadèr CR, Mansouri Taleghani B, Bacher U, and Pabst T
- Abstract
(1) Background: High-dose chemotherapy (HDCT) before autologous stem cell transplantation (ASCT) in acute myeloid leukemia (AML) patients predominantly combines busulfan with cyclophosphamide or melphalan. Treosulfan compares favorably regarding lower inter-individual bioavailability and neurotoxicity, but so far, had not been studied before ASCT in AML. (2) Methods: This single-center study investigated AML patients undergoing ASCT in CR1 between November 2017 and September 2020. The first 16 patients received busulfan 16 mg/kg b.w. (days -5 to -2) and melphalan 140 mg/m
2 (day -1) (BuMel). In a subsequent (TreoMel) cohort, 20 patients received treosulfan 14 g/m2 (days -4 to -2) and melphalan. Plasma concentrations of busulfan and treosulfan were determined by mass spectrometry. (3) Results: Neutrophil engraftment and platelet recovery were similar, and PFS and OS were comparable. In only the BuMel cohort, patients reported central nervous toxicities, including seizures (6%) and encephalopathy (12%). The mean AUC for busulfan was 1471.32 μM*min, and for treosulfan it was 836.79 mg/L*h, with ranges of 804.1-2082 μM*min and 454.2-1402 mg/L*h. The peak values for busulfan ranged between 880.19-1734 μg/L and for treosulfan between 194.3-489.25 mg/L. (4) Conclusions: TreoMel appears to be safe and effective for pre-ASCT treatment in AML patients. Due to considerable interindividual biovariability, pharmacologic monitoring may also be warranted for the use of treosulfan.- Published
- 2022
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21. Maca against Echinococcosis?-A Reverse Approach from Patient to In Vitro Testing.
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Karpstein T, Chaudhry S, Bresson-Hadni S, Hayoz M, Boubaker G, Hemphill A, Rufener R, Kaethner M, Schindler I, Aebi Y, Cunha AS, Largiadèr CR, and Lundström-Stadelmann B
- Abstract
Drug-based treatment of alveolar echinococcosis (AE) with benzimidazoles is in most cases non-curative, thus has to be taken lifelong. Here, we report on a 56-year-old male AE patient who received standard benzimidazole treatment and biliary plastic stents, and additionally self-medicated himself with the Peruvian plant extract Maca ( Lepidium meyenii ). After 42 months, viable parasite tissue had disappeared. Based on this striking observation, the anti-echinococcal activity of Maca was investigated in vitro and in mice experimentally infected with Echinococcus multilocularis metacestodes. Albendazole (ABZ)-treated mice and mice treated with an ABZ+Maca combination exhibited a significantly reduced parasite burden compared to untreated or Maca-treated mice. As shown by a newly established UHPLC-MS/MS-based measurement of ABZ-metabolites, the presence of Maca during the treatment did not alter ABZ plasma levels. In vitro assays corroborated these findings, as exposure to Maca had no notable effect on E. multilocularis metacestodes, and in cultures of germinal layer cells, possibly unspecific, cytotoxic effects of Maca were observed. However, in the combined treatments, Maca inhibited the activity of ABZ in vitro. While Maca had no direct anti-parasitic activity, it induced in vitro proliferation of murine spleen cells, suggesting that immunomodulatory properties could have contributed to the curative effect seen in the patient.
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- 2021
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22. The Swiss Primary Hypersomnolence and Narcolepsy Cohort study (SPHYNCS): Study protocol for a prospective, multicentre cohort observational study.
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Dietmann A, Wenz E, van der Meer J, Ringli M, Warncke JD, Edwards E, Schmidt MH, Bernasconi CA, Nirkko A, Strub M, Miano S, Manconi M, Acker J, von Manitius S, Baumann CR, Valko PO, Yilmaz B, Brunner AD, Tzovara A, Zhang Z, Largiadèr CR, Tafti M, Latorre D, Sallusto F, Khatami R, and Bassetti CLA
- Subjects
- Cohort Studies, Humans, Multicenter Studies as Topic, Observational Studies as Topic, Prospective Studies, Switzerland, Disorders of Excessive Somnolence diagnosis, Disorders of Excessive Somnolence etiology, Disorders of Excessive Somnolence therapy, Narcolepsy diagnosis, Narcolepsy therapy
- Abstract
Narcolepsy type 1 (NT1) is a disorder with well-established markers and a suspected autoimmune aetiology. Conversely, the narcoleptic borderland (NBL) disorders, including narcolepsy type 2, idiopathic hypersomnia, insufficient sleep syndrome and hypersomnia associated with a psychiatric disorder, lack well-defined markers and remain controversial in terms of aetiology, diagnosis and management. The Swiss Primary Hypersomnolence and Narcolepsy Cohort Study (SPHYNCS) is a comprehensive multicentre cohort study, which will investigate the clinical picture, pathophysiology and long-term course of NT1 and the NBL. The primary aim is to validate new and reappraise well-known markers for the characterization of the NBL, facilitating the diagnostic process. Seven Swiss sleep centres, belonging to the Swiss Narcolepsy Network (SNaNe), joined the study and will prospectively enrol over 500 patients with recent onset of excessive daytime sleepiness (EDS), hypersomnia or a suspected central disorder of hypersomnolence (CDH) during a 3-year recruitment phase. Healthy controls and patients with EDS due to severe sleep-disordered breathing, improving after therapy, will represent two control groups of over 50 patients each. Clinical and electrophysiological (polysomnography, multiple sleep latency test, maintenance of wakefulness test) information, and information on psychomotor vigilance and a sustained attention to response task, actigraphy and wearable devices (long-term monitoring), and responses to questionnaires will be collected at baseline and after 6, 12, 24 and 36 months. Potential disease markers will be searched for in blood, cerebrospinal fluid and stool. Analyses will include quantitative hypocretin measurements, proteomics/peptidomics, and immunological, genetic and microbiota studies. SPHYNCS will increase our understanding of CDH and the relationship between NT1 and the NBL. The identification of new disease markers is expected to lead to better and earlier diagnosis, better prognosis and personalized management of CDH., (© 2021 The Authors. Journal of Sleep Research published by John Wiley & Sons Ltd on behalf of European Sleep Research Society.)
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- 2021
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23. Haplotype structure defines effects of common DPYD variants c.85T > C (rs1801265) and c.496A > G (rs2297595) on dihydropyrimidine dehydrogenase activity: Implication for 5-fluorouracil toxicity.
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Hamzic S, Schärer D, Offer SM, Meulendijks D, Nakas C, Diasio RB, Fontana S, Wehrli M, Schürch S, Amstutz U, and Largiadèr CR
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- Fluorouracil adverse effects, Genotype, Haplotypes, Humans, Dihydrouracil Dehydrogenase (NADP) genetics, Drug-Related Side Effects and Adverse Reactions
- Abstract
Aims: The aim of this study was to identify risk variants and haplotypes that impair dihydropyrimidine dehydrogenase (DPD) activity and are, therefore, candidate risk variants for severe toxicity to 5-fluorouracil (5-FU) chemotherapy., Methods: Plasma dihydrouracil/uracil (UH
2 /U) ratios were measured as a population marker for DPD activity in a total of 1382 subjects from 4 independent studies. Genotype and haplotype correlations with UH2 /U ratios were assessed., Results: Significantly lower UH2 /U ratios (panova < 2 × 10-16 ) were observed in carriers of the 4 well-studied 5-FU toxicity risk variants with mean differences (MD) of -43.7% for DPYD c.1905 + 1G > A (rs3918290), -46.0% for DPYD c.1679T > G (rs55886062), -37.1%, for DPYD c.2846A > T (rs67376798), and -13.2% for DPYD c.1129-5923C > G (rs75017182). An additional variant, DPYD c.496A > G (rs2297595), was also associated with lower UH2 /U ratios (P < .0001, MD: -12.6%). A haplotype analysis was performed for variants in linkage disequilibrium with c.496A > G, which consisted of the common variant c.85T > C (rs1801265) and the risk variant c.1129-5923C > G. Both haplotypes carrying c.496A > G were associated with decreased UH2 /U ratios (H3, P = .003, MD: -9.6%; H5, P = .002, MD: -16.9%). A haplotype carrying only the variant c.85T > C (H2) was associated with elevated ratios (P = .004, MD: +8.6%)., Conclusions: Based on our data, DPYD-c.496A > G is a strong candidate risk allele for 5-FU toxicity. Our data suggest that DPYD-c.85T > C might be protective; however, the deleterious impacts of the linked alleles c.496A > G and c.1129-5923C > G likely limit this effect in patients. The possible protective effect of c.85T > C and linkage disequilibrium with c.496A > G and c.1129-5923C > G may have hampered prior association studies and should be considered in future clinical studies., (© 2021 The Authors. British Journal of Clinical Pharmacology published by John Wiley & Sons Ltd on behalf of British Pharmacological Society.)- Published
- 2021
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24. Annual incidence and severity of acute episodes in hereditary thrombotic thrombocytopenic purpura.
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Tarasco E, Bütikofer L, Friedman KD, George JN, Hrachovinova I, Knöbl PN, Matsumoto M, von Krogh AS, Aebi-Huber I, Cermakova Z, Górska-Kosicka M, Jalowiec KA, Largiadèr CR, Prohászka Z, Sinkovits G, Windyga J, Lämmle B, and Kremer Hovinga JA
- Subjects
- Adolescent, Adult, Age of Onset, Aged, Child, Child, Preschool, Female, Humans, Infant, Infant, Newborn, Male, Middle Aged, Severity of Illness Index, Blood Component Transfusion, Genetic Diseases, Inborn epidemiology, Genetic Diseases, Inborn therapy, Plasma, Purpura, Thrombotic Thrombocytopenic epidemiology, Purpura, Thrombotic Thrombocytopenic therapy, Registries
- Abstract
Hereditary thrombotic thrombocytopenic purpura (hTTP) is a rare thrombotic microangiopathy characterized by severe congenital ADAMTS13 deficiency and recurring acute episodes causing morbidity and premature death. Information on the annual incidence and severity of acute episodes in patients with hTTP is largely lacking. This study reports prospective data on 87 patients from the Hereditary TTP Registry (clinicaltrials.gov #NCT01257269) for survival, frequency, and severity of acute episodes from enrollment until December 2019. The 87 patients, followed up for a median of 4.2 years (range, 0.01-15 years), had a median age at overt disease onset and at clinical diagnosis of 4.6 years and 18 years (range, 0.0-70 years for both), respectively. Forty-three patients received regular plasma prophylaxis, whereas 22 did not, and treatment changed over time or was unknown in the remaining 22. Forty-three patients experienced 131 acute episodes, of which 91 (69%) occurred in patients receiving regular prophylaxis. This resulted in an annual incidence of acute episodes of 0.36 (95% confidence interval [CI], 0.29-0.44) with regular plasma treatment and of 0.41 (95% CI, 0.30-0.56) without regular plasma treatment. More than one-third of acute episodes (n = 51) were documented in children <10 years of age at enrollment and were often triggered by infections. Their annual incidence of acute episodes was significantly higher than in patients aged >40 years (1.18 [95% CI, 0.88-1.55] vs 0.14 [95% CI, 0.08-0.23]). The prophylactic plasma infusion regimens used were insufficient to prevent acute episodes in many patients. Such regimens are burdensome, and caregivers, patients, and their guardians are reluctant to start regular plasma infusions, from which children particularly would benefit., (© 2021 by The American Society of Hematology.)
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- 2021
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25. Accuracy of serological testing for SARS-CoV-2 antibodies: First results of a large mixed-method evaluation study.
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Brigger D, Horn MP, Pennington LF, Powell AE, Siegrist D, Weber B, Engler O, Piezzi V, Damonti L, Iseli P, Hauser C, Froehlich TK, Villiger PM, Bachmann MF, Leib SL, Bittel P, Fiedler M, Largiadèr CR, Marschall J, Stalder H, Kim PS, Jardetzky TS, Eggel A, and Nagler M
- Subjects
- Adult, Aged, Aged, 80 and over, Enzyme-Linked Immunosorbent Assay, Female, Humans, Male, Middle Aged, Prospective Studies, Antibodies, Viral blood, COVID-19 Serological Testing methods, SARS-CoV-2 immunology
- Abstract
Background: Serological immunoassays that can identify protective immunity against SARS-CoV-2 are needed to adapt quarantine measures, assess vaccination responses, and evaluate donor plasma. To date, however, the utility of such immunoassays remains unclear. In a mixed-design evaluation study, we compared the diagnostic accuracy of serological immunoassays that are based on various SARS-CoV-2 proteins and assessed the neutralizing activity of antibodies in patient sera., Methods: Consecutive patients admitted with confirmed SARS-CoV-2 infection were prospectively followed alongside medical staff and biobank samples from winter 2018/2019. An in-house enzyme-linked immunosorbent assay utilizing recombinant receptor-binding domain (RBD) of the SARS-CoV-2 spike protein was developed and compared to three commercially available enzyme-linked immunosorbent assays (ELISAs) targeting the nucleoprotein (N), the S1 domain of the spike protein (S1), and a lateral flow immunoassay (LFI) based on full-length spike protein. Neutralization assays with live SARS-CoV-2 were performed., Results: One thousand four hundred and seventy-seven individuals were included comprising 112 SARS-CoV-2 positives (defined as a positive real-time PCR result; prevalence 7.6%). IgG seroconversion occurred between day 0 and day 21. While the ELISAs showed sensitivities of 88.4% for RBD, 89.3% for S1, and 72.9% for N protein, the specificity was above 94% for all tests. Out of 54 SARS-CoV-2 positive individuals, 96.3% showed full neutralization of live SARS-CoV-2 at serum dilutions ≥ 1:16, while none of the 6 SARS-CoV-2-negative sera revealed neutralizing activity., Conclusions: ELISAs targeting RBD and S1 protein of SARS-CoV-2 are promising immunoassays which shall be further evaluated in studies verifying diagnostic accuracy and protective immunity against SARS-CoV-2., (© 2020 The Authors. Allergy published by European Academy of Allergy and Clinical Immunology and John Wiley & Sons Ltd.)
- Published
- 2021
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26. Insights from the Hereditary Thrombotic Thrombocytopenic Purpura Registry: Discussion of Key Findings Based on Individual Cases from Switzerland.
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Kremer Hovinga JA, Braschler TR, Buchkremer F, Farese S, Hengartner H, Lovey PY, Largiadèr CR, Mansouri Taleghani B, and Tarasco E
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- Female, Humans, Male, Registries, Switzerland, Purpura, Thrombotic Thrombocytopenic diagnosis
- Abstract
The Hereditary TTP Registry is an international cohort study for patients with a confirmed or suspected diagnosis of hereditary thrombotic thrombocytopenic purpura (hTTP) and their family members. Hereditary TTP is an ultra-rare blood disorder (prevalence of ∼1-2 cases per million), the result of autosomal-recessively inherited congenital ADAMTS13 (a disintegrin and metalloproteinase with a thrombospondin type 1 motif, member 13) deficiency (ADAMTS13 activity <10% of the normal), and associated with yet many unanswered questions. Until December 2017, the Hereditary TTP Registry had enrolled 123 confirmed hTTP patients. Their median age at disease onset was 4.5 years (range: 0-70) and at clinical diagnosis 16.7 years (range: 0-69), a difference that highlights the existing awareness gap in recognizing hTTP. The systematic collection of clinical data of individual patients revealed their substantial baseline comorbidities, as a consequence of recurring TTP episodes in the past. Most notable was the high proportion of patients having suffered from premature arterial thrombotic events, mainly transient ischemic attacks, ischemic strokes, and to a lesser extent myocardial infarctions. At 40 to 50 years of age and above, more than 50% of patients had suffered from at least one such event, and many had experienced arterial thrombotic events despite regular plasma infusions every 2 to 3 weeks that supplements the missing plasma ADAMTS13. The article by van Dorland et al. (Haematologica 2019;104(10):2107-2115) and the ongoing Hereditary TTP Registry cohort study were recognized with the Günter Landbeck Excellence Award at the 50th Hemophilia Symposium in Hamburg in November 2019, the reason to present the Hereditary TTP Registry in more detail here., Competing Interests: J.A.K.H. is a member of advisory board of Shire, member of the Takeda group of companies and of Ablynx, now part of Sanofi. All honoraria are paid to her employer, Insel Gruppe AG, Bern, Switzerland. The other authors have nothing to declare., (Thieme. All rights reserved.)
- Published
- 2020
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27. Genome-Wide Association Study of Metamizole-Induced Agranulocytosis in European Populations.
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Cismaru AL, Rudin D, Ibañez L, Liakoni E, Bonadies N, Kreutz R, Carvajal A, Lucena MI, Martin J, Sancho Ponce E, Molokhia M, Eriksson N, EuDAC Collaborators, Krähenbühl S, Largiadèr CR, Haschke M, Hallberg P, Wadelius M, and Amstutz U
- Subjects
- Adult, Aged, Aged, 80 and over, Agranulocytosis metabolism, Biomarkers, Pharmacological, Case-Control Studies, Dipyrone pharmacology, Europe epidemiology, Female, Genetic Predisposition to Disease genetics, Genome-Wide Association Study, Germany, Humans, Male, Middle Aged, Neutropenia metabolism, Retrospective Studies, Switzerland, Agranulocytosis genetics, Dipyrone adverse effects, Neutropenia genetics
- Abstract
Agranulocytosis is a rare yet severe idiosyncratic adverse drug reaction to metamizole, an analgesic widely used in countries such as Switzerland and Germany. Notably, an underlying mechanism has not yet been fully elucidated and no predictive factors are known to identify at-risk patients. With the aim to identify genetic susceptibility variants to metamizole-induced agranulocytosis (MIA) and neutropenia (MIN), we conducted a retrospective multi-center collaboration including cases and controls from three European populations. Association analyses were performed using genome-wide genotyping data from a Swiss cohort (45 cases, 191 controls) followed by replication in two independent European cohorts (41 cases, 273 controls) and a joint discovery meta-analysis. No genome-wide significant associations ( p < 1 × 10
-7 ) were observed in the Swiss cohort or in the joint meta-analysis, and no candidate genes suggesting an immune-mediated mechanism were identified. In the joint meta-analysis of MIA cases across all cohorts, two candidate loci on chromosome 9 were identified, rs55898176 (OR = 4.01, 95%CI: 2.41-6.68, p = 1.01 × 10-7 ) and rs4427239 (OR = 5.47, 95%CI: 2.81-10.65, p = 5.75 × 10-7 ), of which the latter is located in the SVEP1 gene previously implicated in hematopoiesis. This first genome-wide association study for MIA identified suggestive associations with biological plausibility that may be used as a stepping-stone for post-GWAS analyses to gain further insight into the mechanism underlying MIA.- Published
- 2020
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28. A Novel Nomenclature for Repeat Motifs in the Thymidylate Synthase Enhancer Region and Its Relevance for Pharmacogenetic Studies.
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Schaerer D, Froehlich TK, Hamzic S, Offer SM, Diasio RB, Joerger M, Amstutz U, and Largiadèr CR
- Abstract
Inhibition of thymidylate synthase (TS) is the primary mode of action for 5-fluorouracil (5FU) chemotherapy. TS expression is modulated by a variable number of tandem repeats in the TS enhancer region (TSER) located upstream of the TS gene ( TYMS ). Variability in the TSER has been suggested to contribute to 5FU-induced adverse events. However, the precise genetic associations remain largely undefined due to high polymorphism and ambiguity in defining genotypes. To assess toxicity associations, we sequenced the TSER in 629 cancer patients treated with 5FU. Of the 13 alleles identified, few could be unambiguously named using current TSER-nomenclature. We devised a concise and unambiguous systematic naming approach for TSER-alleles that encompasses all known variants. After applying this comprehensive naming system to our data, we demonstrated that the number of upstream stimulatory factor (USF1-)binding sites in the TSER was significantly associated with gastrointestinal toxicity in 5FU treatment.
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- 2020
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29. Associations of the intestinal microbiome with the complement system in neovascular age-related macular degeneration.
- Author
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Zysset-Burri DC, Keller I, Berger LE, Largiadèr CR, Wittwer M, Wolf S, and Zinkernagel MS
- Abstract
Age-related macular degeneration (AMD) is a leading cause of severe vision loss in the aged population. The etiology of AMD is multifactorial including nutritional factors, genetic variants mainly in the complement pathway, environmental risk factors and alterations in the intestinal microbiome. However, it remains unexplored whether there is an interdependency of these factors leading to the development of AMD. To investigate this issue, a shotgun metagenomics analysis of 57 neovascular AMD and 58 healthy controls as well as of 16 complement C3-deficient mice and 16 wildtypes was performed. Whereas the class Negativicutes was more abundant in patients, the genus Oscillibacter and species Bacteroides had a significantly higher prevalence in persons without AMD. Similar taxonomic features were identified that distinguished wildtype mice from C3-deficient mice. Moreover, several purine signaling pathways were associated with both, neovascular AMD and C3 deficiency. While SNPs within the complement factor B gene were more abundant in controls, SNPs within the high temperature requirement A serine peptidase 1 and complement factor H (CFH) genes were associated with neovascular AMD. Using a classification model, Negativicutes was identified as a potential biomarker for AMD and furthermore, it positively correlated with CFH. This study suggests an association between the intestinal microbiome and the complement system in neovascular AMD., Competing Interests: Competing interestsThe authors declare no competing interests., (© The Author(s) 2020.)
- Published
- 2020
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30. High-Throughput Sequencing to Investigate Associations Between HLA Genes and Metamizole-Induced Agranulocytosis.
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Cismaru AL, Grimm L, Rudin D, Ibañez L, Liakoni E, Bonadies N, Kreutz R, Hallberg P, Wadelius M, Haschke M, Largiadèr CR, and Amstutz U
- Abstract
Background and Objective: Agranulocytosis is a rare and potentially life-threatening complication of metamizole (dipyrone) intake that is characterized by a loss of circulating neutrophil granulocytes. While the mechanism underlying this adverse drug reaction is not well understood, involvement of the immune system has been suggested. In addition, associations between genetic variants in the Human Leukocyte Antigen (HLA) region and agranulocytosis induced by other drugs have been reported. The aim of the present study was to assess whether genetic variants in classical HLA genes are associated with the susceptibility to metamizole-induced agranulocytosis (MIA) in a European population by targeted resequencing of eight HLA genes. Design: A case-control cohort of Swiss patients with a history of neutropenia or agranulocytosis associated with metamizole exposure ( n = 53), metamizole-tolerant ( n = 39) and unexposed controls ( n = 161) was recruited for this study. A high-throughput resequencing (HTS) and high-resolution typing method was used to sequence and analyze eight HLA loci in a discovery subset of this cohort ( n = 31 cases, n = 38 controls). Identified candidate alleles were investigated in the full Swiss cohort as well as in two independent cohorts from Germany and Spain using HLA imputation from genome-wide SNP array data. In addition, variant calling based on HTS data was performed in the discovery subset for the class I genes HLA-A , - B , and - C using the HLA-specific mapper hla-mapper . Results: Eight candidate alleles ( p < 0.05) were identified in the discovery subset, of which HLA - C
∗ 04:01 was associated with MIA in the full Swiss cohort ( p < 0.01) restricted to agranulocytosis (ANC < 0.5 × 109 /L) cases. However, no candidate allele showed a consistent association in the Swiss, German and Spanish cohorts. Analysis of individual sequence variants in class I genes produced consistent results with HLA typing but did not reveal additional small nucleotide variants associated with MIA. Conclusion: Our results do not support an HLA-restricted T cell-mediated immune mechanism for MIA. However, we established an efficient high-resolution (three-field) eight-locus HTS HLA resequencing method to interrogate the HLA region and demonstrated the feasibility of its application to pharmacogenetic studies., (Copyright © 2020 Cismaru, Grimm, Rudin, Ibañez, Liakoni, Bonadies, Kreutz, Hallberg, Wadelius, EuDAC Collaborators, Haschke, Largiadèr and Amstutz.)- Published
- 2020
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31. Effects of Freezing and Thawing Procedures on Selected Clinical Chemistry Parameters in Plasma.
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Freiburghaus K, Leichtle AB, Nakas CT, Fiedler GM, and Largiadèr CR
- Subjects
- Alanine Transaminase blood, C-Reactive Protein analysis, Freezing adverse effects, Humans, L-Lactate Dehydrogenase blood, Lipase blood, Reproducibility of Results, Uric Acid blood, Plasma chemistry, Serum Albumin analysis, Specimen Handling adverse effects
- Abstract
Introduction: Measurements from frozen sample collections are important key indicators in clinical studies. It is a prime concern of biobanks and laboratories to minimize preanalytical bias and variance through standardization. In this study, we aimed at assessing the effects of different freezing and thawing conditions on the reproducibility of medical routine parameters from frozen samples. Materials and Methods: In total, 12 pooled samples were generated from leftover lithium heparinized plasma samples from clinical routine testing. Aliquots of the pools were frozen using three freezing methods (in carton box at -80°C, flash freezing in liquid nitrogen, and controlled-rate freezing [CRF]) and stored at -80°C. After 3 days, samples were thawed using two methods (30 minutes at room temperature or water bath at 25°C for 3 minutes). Ten clinical chemistry laboratory parameters were measured before (baseline) and after freeze-thaw treatment: total calcium, potassium, sodium, alanine aminotransferase, lactate dehydrogenase (LDH), lipase, uric acid, albumin, c-reactive protein (CRP), and total protein. We evaluated the influence of the different preanalytical treatments on the test results and compared each condition with nonfrozen baseline measurements. Results: We found no significant differences between freezing methods for all tested parameters. Only LDH was significantly affected by thawing with fast-rate thawing being closer to baseline than slow-rate thawing. Potassium, LDH, lipase, uric acid, albumin, and CRP values were significantly changed after freezing and thawing compared with unfrozen samples. The least prominent changes compared with unfrozen baseline measurements were obtained when a CRF protocol of the local biobank and fast thawing was applied. However, the observed changes between baseline and frozen samples were smaller than the measurement uncertainty for 9 of the 10 parameters. Discussion: Changes introduced through freezing-thawing were small and not of clinical importance. A slight statistically based preference toward results from slow CRF and fast thawing of plasma being closest to unfrozen samples could be supported.
- Published
- 2020
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32. Integrating Pharmacogenetic Decision Support into a Clinical Information System.
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Tippenhauer K, Philips M, Largiadèr CR, Sariyar M, and Bürkle T
- Subjects
- Decision Support Systems, Clinical, Electronic Health Records, Pharmacogenetics, Software, Pharmacogenomic Testing
- Abstract
Pharmacogenetic testing can prevent adverse drug events but has rarely found its way into clinical routine. One reason is the lack of tools for smooth and automatable integration of pharmacogenetic knowledge into existing processes. Especially, electronic medical records (EMR) represent a suitable environment for such tools. We developed a modular service-oriented prototype of a pharmacogenetic decision support system within an EMR system of the Bern University Hospital. Here, we present the component architecture of our system and discuss issues required for generalizing our results.
- Published
- 2020
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33. Evaluating the role of ENOSF1 and TYMS variants as predictors in fluoropyrimidine-related toxicities: An IPD meta-analysis.
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Hamzic S, Kummer D, Froehlich TK, Joerger M, Aebi S, Palles C, Thomlinson I, Meulendijks D, Schellens JHM, García-González X, López-Fernández LA, Amstutz U, and Largiadèr CR
- Subjects
- Humans, Neoplasms genetics, Antimetabolites, Antineoplastic adverse effects, Capecitabine adverse effects, Fluorouracil adverse effects, Hand-Foot Syndrome genetics, Hydro-Lyases genetics, Neoplasms drug therapy, Thymidylate Synthase genetics
- Abstract
To assess the proposed associations of the c.742-227G>A (rs2612091) polymorphism within the Enolase Superfamily Member 1 gene (ENOSF1) and two variants in the adjacent Thymidylate Synthase gene (TYMS): the 5'VNTR 28bp-repeat (rs45445694) and 3'UTR 6bp-indel (rs11280056) with severe toxicity in fluoropyrimidine-treated cancer patients, we performed an individual patient data meta-analysis. Only studies investigating all three-abovementioned variants with fluoropyrimidine-related toxicities were considered for meta-analysis. Associations were tested individually for each study using multivariate regression. Meta-analysis was performed using a random-effects model. One-stage multivariate regressions including tests for independent SNP effects were applied to investigate individual effects of the variants. Multivariate haplotype regression analyses were performed on a pooled dataset to test multi-SNP effects. Of four studies including 2'067 patients, 1'912 were eligible for meta-analysis. All variants were exclusively associated with severe hand-foot-syndrome (HFS) (TYMS 2R: OR = 1.50, p = 0.0002; TYMS 6bp-ins: OR = 1.42 p = 0.0036; ENOSF1 c.742-227G: OR = 1.64 p < 0.0001, per allele). We observed independent effects for ENOSF1 c.742-227G>A and the TYMS 28bp-repeat: each toxicity-associated allele increased the risk for severe HFS (OR = 1.32 per allele, p < 0.0001). Patients homozygous for both variants were at the 3-fold higher risk for severe HFS compared to wild-type patients. Our results confirm an essential role for ENOSF1 c.742-227G and TYMS 2R-alleles in the development of fluoropyrimidine-related HFS. This suggests an important function of these genes in the development of severe HFS. Furthermore, these variants might help stratify patients in studies investigating measures of HFS prevention., Competing Interests: Declaration of Competing Interest The authors declare no potential conflicts of interest., (Copyright © 2019 The Authors. Published by Elsevier Ltd.. All rights reserved.)
- Published
- 2020
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34. Dihydropyrimidine Dehydrogenase Testing prior to Treatment with 5-Fluorouracil, Capecitabine, and Tegafur: A Consensus Paper.
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Wörmann B, Bokemeyer C, Burmeister T, Köhne CH, Schwab M, Arnold D, Blohmer JU, Borner M, Brucker S, Cascorbi I, Decker T, de Wit M, Dietz A, Einsele H, Eisterer W, Folprecht G, Hilbe W, Hoffmann J, Knauf W, Kunzmann V, Largiadèr CR, Lorenzen S, Lüftner D, Moehler M, Nöthen MM, Pox C, Reinacher-Schick A, Scharl A, Schlegelberger B, Seufferlein T, Sinn M, Stroth M, Tamm I, Trümper L, Wilhelm M, Wöll E, and Hofheinz RD
- Subjects
- Antimetabolites, Antineoplastic adverse effects, Austria, Capecitabine administration & dosage, Capecitabine adverse effects, Consensus, Female, Fluorouracil adverse effects, Genetic Testing standards, Genotype, Germany, Humans, Male, Mutation, Neoplasms genetics, Phenotype, Practice Guidelines as Topic, Switzerland, Tegafur administration & dosage, Tegafur adverse effects, Antimetabolites, Antineoplastic administration & dosage, Dihydrouracil Dehydrogenase (NADP) genetics, Fluorouracil administration & dosage, Genetic Testing methods, Neoplasms drug therapy
- Abstract
Background: 5-Fluorouracil (FU) is one of the most commonly used cytostatic drugs in the systemic treatment of cancer. Treatment with FU may cause severe or life-threatening side effects and the treatment-related mortality rate is 0.2-1.0%., Summary: Among other risk factors associated with increased toxicity, a genetic deficiency in dihydropyrimidine dehydrogenase (DPD), an enzyme responsible for the metabolism of FU, is well known. This is due to variants in the DPD gene (DPYD). Up to 9% of European patients carry a DPD gene variant that decreases enzyme activity, and DPD is completely lacking in approximately 0.5% of patients. Here we describe the clinical and genetic background and summarize recommendations for the genetic testing and tailoring of treatment with 5-FU derivatives. The statement was developed as a consensus statement organized by the German Society for Hematology and Medical Oncology in cooperation with 13 medical associations from Austria, Germany, and Switzerland. Key Messages: (i) Patients should be tested for the 4 most common genetic DPYD variants before treatment with drugs containing FU. (ii) Testing forms the basis for a differentiated, risk-adapted algorithm with recommendations for treatment with FU-containing drugs. (iii) Testing may optionally be supplemented by therapeutic drug monitoring., (© 2020 S. Karger AG, Basel.)
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- 2020
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35. The International Hereditary Thrombotic Thrombocytopenic Purpura Registry: key findings at enrollment until 2017.
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van Dorland HA, Taleghani MM, Sakai K, Friedman KD, George JN, Hrachovinova I, Knöbl PN, von Krogh AS, Schneppenheim R, Aebi-Huber I, Bütikofer L, Largiadèr CR, Cermakova Z, Kokame K, Miyata T, Yagi H, Terrell DR, Vesely SK, Matsumoto M, Lämmle B, Fujimura Y, and Kremer Hovinga JA
- Subjects
- Adolescent, Adult, Age of Onset, Aged, Child, Child, Preschool, Female, Humans, Infant, Infant, Newborn, Male, Middle Aged, ADAMTS13 Protein blood, ADAMTS13 Protein genetics, Alleles, Heterozygote, Homozygote, Mutation, Purpura, Thrombotic Thrombocytopenic enzymology, Purpura, Thrombotic Thrombocytopenic genetics
- Abstract
Congenital thrombotic thrombocytopenic purpura is an autosomal recessive inherited disease with a clinically heterogeneous course and an incompletely understood genotype-phenotype correlation. In 2006, the Hereditary TTP Registry started recruitment for a study which aimed to improve the understanding of this ultra-rare disease. The objective of this study is to present characteristics of the cohort until the end of 2017 and to explore the relationship between overt disease onset and ADAMTS13 activity with emphasis on the recurring ADAMTS13 c.4143_4144dupA mutation. Diagnosis of congenital thrombotic thrombocytopenic purpura was confirmed by severely deficient ADAMTS13 activity (≤10% of normal) in the absence of a functional inhibitor and the presence of ADAMTS13 mutations on both alleles. By the end of 2017, 123 confirmed patients had been enrolled from Europe (n=55), Asia (n=52, 90% from Japan), the Americas (n=14), and Africa (n=2). First recognized disease manifestation occurred from around birth up to the age of 70 years. Of the 98 different ADAMTS13 mutations detected, c.4143_4144dupA (exon 29; p.Glu1382Argfs*6) was the most frequent mutation, present on 60 of 246 alleles. We found a larger proportion of compound heterozygous than homozygous carriers of ADAMTS13 c.4143_4144dupA with overt disease onset at < 3 months of age (50% vs 37%), despite the fact that ADAMTS13 activity was <1% in 18 of 20 homozygous, but in only 8 of 14 compound heterozygous carriers. An evaluation of overt disease onset in all patients with an available sensitive ADAMTS13 activity assay (n=97) shows that residual ADAMTS13 activity is not the only determinant of age at first disease manifestation. Registered at clinicaltrials.gov identifier NCT01257269 ., (Copyright© 2019 Ferrata Storti Foundation.)
- Published
- 2019
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36. Metabolomics by UHPLC-MS: benefits provided by complementary use of Q-TOF and QQQ for pathway profiling.
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Freiburghaus K, Largiadèr CR, Stettler C, Fiedler GM, Bally L, and Bovet C
- Subjects
- Citric Acid Cycle, Diabetes Mellitus, Type 1 metabolism, Humans, Limit of Detection, Male, Metabolomics standards, Physical Conditioning, Human, Purines metabolism, Spectrometry, Mass, Electrospray Ionization standards, Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization standards, Diabetes Mellitus, Type 1 blood, Metabolome, Metabolomics methods, Spectrometry, Mass, Electrospray Ionization methods, Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization methods
- Abstract
Introduction: Non-targeted metabolic profiling using high-resolution mass spectrometry (HRMS) is a standard approach for pathway identification despite technical limitations., Objectives: To assess the performance of combining targeted quadrupole (QQQ) analysis with HRMS for in-depth pathway profiling., Methods: Serum of exercising patients with type 1 diabetes (T1D) was profiled using targeted and non-targeted assays., Results: Non-targeted analysis yielded a broad unbiased metabolic profile, targeted analysis increased coverage of purine metabolism (twofold) and TCA cycle (three metabolites)., Conclusion: Our screening strategy combined the benefits of the unbiased full-scan HRMS acquisition with the deeper insight into specific pathways by large-scale QQQ analysis.
- Published
- 2019
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37. Genotype-guided fluoropyrimidine dosing: ready for implementation.
- Author
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Amstutz U and Largiadèr CR
- Subjects
- Genotype, Humans, Prospective Studies, Anticoagulants, Neoplasms
- Published
- 2018
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38. Come a long way, still a ways to go: from predicting and preventing fluoropyrimidine toxicity to increased efficacy?
- Author
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Hamzic S, Amstutz U, and Largiadèr CR
- Subjects
- Female, Humans, Male, Pharmacogenetics methods, Polymorphism, Single Nucleotide genetics, Capecitabine adverse effects, Drug-Related Side Effects and Adverse Reactions genetics, Fluorouracil adverse effects
- Published
- 2018
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39. An SSP-PCR method for the rapid detection of disease-associated alleles HLA-A*29 and HLA-B*51.
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Amstutz U, Schaerer D, Andrey G, Wirthmueller U, and Largiadèr CR
- Abstract
HLA-A*29 and HLA-B*51 are associated with birdshot uveitis and Behçet's disease, respectively, and are used as a diagnostic criterion in patients with suspected disease, requiring their detection in diagnostic laboratories. While commercial tests for individual HLA alleles are available for other disease-associated HLA variants, no similar allele-specific assays are available for HLA-A*29 and HLA-B*51. Here, we report sequence-specific priming-polymerase chain reaction (SSP-PCR) methods for the detection of HLA-A*29 and HLA-B*51 using a single PCR reaction per allele. The assays were tested in 30 and 32 previously HLA-typed samples, respectively, representing >97% of HLA-A alleles and >93% of HLA-B alleles in a European population. A concordance of 100% was observed with previous typing results, validating these methods for use in a diagnostic or research context., (© 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)
- Published
- 2018
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40. Targeted and global pharmacometabolomics in everolimus-based immunosuppression: association of co-medication and lysophosphatidylcholines with dose requirement.
- Author
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Lesche D, Sigurdardottir V, Leichtle AB, Nakas CT, Christians U, Englberger L, Fiedler M, Largiadèr CR, Mohacsi P, and Sistonen J
- Subjects
- Adult, Aged, Biomarkers metabolism, Chromatography, High Pressure Liquid methods, Cytochrome P-450 CYP3A metabolism, Dose-Response Relationship, Drug, Drug Interactions, Drug Therapy, Combination methods, Female, Humans, Immune Tolerance drug effects, Immunologic Deficiency Syndromes drug therapy, Male, Metabolomics, Middle Aged, Molecular Targeted Therapy methods, Mycophenolic Acid metabolism, Tandem Mass Spectrometry methods, Everolimus pharmacology, Heart Transplantation adverse effects, Immunosuppression Therapy methods, Immunosuppressive Agents pharmacology, Lysophosphatidylcholines pharmacology
- Abstract
Introduction: The immunosuppressive therapy with everolimus (ERL) after heart transplantation is characterized by a narrow therapeutic window and a substantial variability in dose requirement. Factors explaining this variability are largely unknown., Objectives: Our aim was to evaluate factors affecting ERL metabolism and to identify novel metabolites associated with the individual ERL dose requirement to elucidate mechanisms underlying ERL dose response variability., Method: We used liquid chromatography coupled with mass spectrometry for quantification of ERL metabolites in 41 heart transplant patients and evaluated the effect of clinical and genetic factors on ERL pharmacokinetics. Non-targeted plasma metabolic profiling by ultra-performance liquid chromatography and high resolution quadrupole-time-of-flight mass spectrometry was used to identify novel metabolites associated with ERL dose requirement., Results: The determination of ERL metabolites revealed differences in metabolite patterns that were independent from clinical or genetic factors. Whereas higher ERL dose requirement was associated with co-administration of sodium-mycophenolic acid and the CYP3A5 expressor genotype, lower dose was required for patients receiving vitamin K antagonists. Global metabolic profiling revealed several novel metabolites associated with ERL dose requirement. One of them was identified as lysophosphatidylcholine (lysoPC) (16:0/0:0). Subsequent targeted analysis revealed that high levels of several lysoPCs were significantly associated with higher ERL dose requirement., Conclusion: For the first time, this study describes distinct ERL metabolite patterns in heart transplant patients and detected potentially new drug-drug interactions. The global metabolic profiling facilitated the discovery of novel metabolites associated with ERL dose requirement that might represent new clinically valuable biomarkers to guide ERL therapy.
- Published
- 2017
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41. Rapid molecular sexing of three-spined sticklebacks, Gasterosteus aculeatus L., based on large Y-chromosomal insertions.
- Author
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Bakker TCM, Giger T, Frommen JG, and Largiadèr CR
- Subjects
- Animals, Female, Male, Microsatellite Repeats, Phenotype, Polymorphism, Single Nucleotide, Sex Determination Analysis veterinary, INDEL Mutation, Sex Determination Analysis methods, Smegmamorpha genetics, Y Chromosome genetics
- Abstract
There is a need for rapid and reliable molecular sexing of three-spined sticklebacks, Gasterosteus aculeatus, the supermodel species for evolutionary biology. A DNA region at the 5' end of the sex-linked microsatellite Gac4202 was sequenced for the X chromosome of six females and the Y chromosome of five males from three populations. The Y chromosome contained two large insertions, which did not recombine with the phenotype of sex in a cross of 322 individuals. Genetic variation (SNPs and indels) within the insertions was smaller than on flanking DNA sequences. Three molecular PCR-based sex tests were developed, in which the first, the second or both insertions were covered. In five European populations (from DE, CH, NL, GB) of three-spined sticklebacks, tests with both insertions combined showed two clearly separated bands on agarose minigels in males and one band in females. The tests with the separate insertions gave similar results. Thus, the new molecular sexing method gave rapid and reliable results for sexing three-spined sticklebacks and is an improvement and/or alternative to existing methods.
- Published
- 2017
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42. The impact of ABCC11 polymorphisms on the risk of early-onset fluoropyrimidine toxicity.
- Author
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Hamzic S, Wenger N, Froehlich TK, Joerger M, Aebi S, Largiadèr CR, and Amstutz U
- Subjects
- Adolescent, Adult, Aged, Aged, 80 and over, Antimetabolites, Antineoplastic adverse effects, Antimetabolites, Antineoplastic therapeutic use, Female, Fluorouracil adverse effects, Fluorouracil therapeutic use, Humans, Leukocytes drug effects, Male, Middle Aged, Pyrimidines therapeutic use, Risk, Young Adult, ATP-Binding Cassette Transporters genetics, Leukopenia chemically induced, Leukopenia genetics, Polymorphism, Single Nucleotide genetics, Pyrimidines adverse effects
- Abstract
A missense variant (c.1637C>T, T546M) in ABCC11 encoding the MRP8 (multidrug resistance protein 8), a transporter of 5-fluorodeoxyuridine monophosphate, has been associated with an increased risk of 5-fluorouracil-related severe leukopenia. To validate this association, we investigated the impact of the ABCC11 variants c.1637C>T, c.538G>A and c.395+1087C>T on the risk of early-onset fluoropyrimidine-related toxicity in 514 cancer patients. The ABCC11 variant c.1637C>T was strongly associated with severe leukopenia in patients carrying risk variants in DPYD, encoding the key fluoropyrimidine-metabolizing enzyme dihydropyrimidine dehydrogenase (odds ratio (OR): 71.0; 95% confidence interval (CI): 2.5-2004.8; P
c.1637C>T*DPYD =0.013). In contrast, in patients without DPYD risk variants, no association with leukopenia (OR: 0.95; 95% CI: 0.34-2.6) or overall fluoropyrimidine-related toxicity (OR: 1.02; 95% CI: 0.5-2.1) was observed. Our study thus suggests that c.1637C>T affects fluoropyrimidine toxicity to leukocytes particularly in patients with high drug exposure, for example, because of reduced fluoropyrimidine catabolism.- Published
- 2017
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43. A UHPLC-MS/MS method for the quantification of 7α-hydroxy-4-cholesten-3-one to assist in diagnosis of bile acid malabsorption.
- Author
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Prost JC, Brunner F, Bovet C, Grob C, Berchtold C, Schlotterbeck G, Kröll D, Largiadèr CR, Fiedler GM, and Juillerat P
- Abstract
Bile acids malabsorption (BAM) is encountered in numerous gastrointestinal pathologies and is a good example of a treatable cause of watery diarrhea after ileal resection. The gold standard for diagnosing BAM is the selenium homocholic acid taurine test (SeHCAT), an expensive and complex analysis. An alternative method is the quantification of 7α-hydroxy-4-cholesten-3-one (C4). Here, we present a simple, ultra high-performance liquid chromatography-tandem mass spectrometry method to measure C4 in human serum. To avoid time consuming sample preparation (e.g., derivatization, solid phase extraction), we used absorption chemistry-based extraction plates. This method demonstrates a lower limit of quantification of 5 ng/mL and is linear over a concentration range from 5 to 300 ng/mL (R
2 = 0.9977). Inaccuracy and imprecision were less than 15%. The validated method is currently used for routine measurement of C4 from serum in patients to confirm BAM diagnosis., (© 2017 The Association for Mass Spectrometry: Applications to the Clinical Lab (MSACL). Published by Elsevier B.V.)- Published
- 2017
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44. Association of the Intestinal Microbiome with the Development of Neovascular Age-Related Macular Degeneration.
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Zinkernagel MS, Zysset-Burri DC, Keller I, Berger LE, Leichtle AB, Largiadèr CR, Fiedler GM, and Wolf S
- Subjects
- Aged, Bacteroides isolation & purification, Case-Control Studies, Female, Humans, Macular Degeneration epidemiology, Male, Middle Aged, Ruminococcus isolation & purification, Gastrointestinal Microbiome, Macular Degeneration microbiology
- Abstract
Age-related macular degeneration (AMD) is the most frequent cause of blindness in the elderly. There is evidence that nutrition, inflammation and genetic risk factors play an important role in the development of AMD. Recent studies suggest that the composition of the intestinal microbiome is associated with metabolic diseases through modulation of inflammation and host metabolism. To investigate whether compositional and functional alterations of the intestinal microbiome are associated with AMD, we sequenced the gut metagenomes of patients with AMD and controls. The genera Anaerotruncus and Oscillibacter as well as Ruminococcus torques and Eubacterium ventriosum were relatively enriched in patients with AMD, whereas Bacteroides eggerthii was enriched in controls. Patient's intestinal microbiomes were enriched in genes of the L-alanine fermentation, glutamate degradation and arginine biosynthesis pathways and decreased in genes of the fatty acid elongation pathway. These findings suggest that modifications in the intestinal microbiome are associated with AMD, inferring that this common sight threatening disease may be targeted by microbiome-altering interventions.
- Published
- 2017
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45. Rs895819 in MIR27A improves the predictive value of DPYD variants to identify patients at risk of severe fluoropyrimidine-associated toxicity.
- Author
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Meulendijks D, Henricks LM, Amstutz U, Froehlich TK, Largiadèr CR, Beijnen JH, de Boer A, Deenen MJ, Cats A, and Schellens JH
- Subjects
- Adult, Aged, Aged, 80 and over, Colorectal Neoplasms pathology, Female, Fluorouracil administration & dosage, Fluorouracil adverse effects, Gene Frequency, Genetic Association Studies, Genotype, Humans, Male, Middle Aged, Polymorphism, Single Nucleotide, Risk, Colorectal Neoplasms drug therapy, Colorectal Neoplasms genetics, Dihydrouracil Dehydrogenase (NADP) genetics, MicroRNAs genetics
- Abstract
The objective of this study was to determine whether genotyping of MIR27A polymorphisms rs895819A>G and rs11671784C>T can be used to improve the predictive value of DPYD variants to identify patients at risk of severe fluoropyrimidine-associated toxicity (FP-toxicity). Patients treated previously in a prospective study with fluoropyrimidine-based chemotherapy were genotyped for rs895819 and rs11671784, and DPYD c.2846A>T, c.1679T>G, c.1129-5923C>G and c.1601G>A. The predictive value of MIR27A variants for early-onset grade ≥3 FP-toxicity, alone or in combination with DPYD variants, was tested in multivariable logistic regression models. Random-effects meta-analysis was performed, including previously published data. A total of 1,592 patients were included. Allele frequencies of rs895819 and rs11671784 were 0.331 and 0.020, respectively. In DPYD wild-type patients, MIR27A variants did not affect risk of FP-toxicity (OR 1.3 for ≥1 variant MIR27A allele vs. none, 95% CI: 0.87-1.82, p = 0.228). In contrast, in patients carrying DPYD variants, the presence of ≥1 rs895819 variant allele was associated with increased risk of FP-toxicity (OR 4.9, 95% CI: 1.24-19.7, p = 0.023). Rs11671784 was not associated with FP-toxicity (OR 2.9, 95% CI: 0.47-18.0, p = 0.253). Patients carrying a DPYD variant and rs895819 were at increased risk of FP-toxicity compared to patients wild type for rs895819 and DPYD (OR 2.4, 95% CI: 1.27-4.37, p = 0.007), while patients with a DPYD variant but without a MIR27A variant were not (OR 0.3 95% CI: 0.06-1.17, p = 0.081). In meta-analysis, rs895819 remained significantly associated with FP-toxicity in DPYD variant allele carriers, OR 5.4 (95% CI: 1.83-15.7, p = 0.002). This study demonstrates the clinical validity of combined MIR27A/DPYD screening to identify patients at risk of severe FP-toxicity., (© 2016 UICC.)
- Published
- 2016
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46. Phenotypic and clinical implications of variants in the dihydropyrimidine dehydrogenase gene.
- Author
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Kuilenburg ABPV, Meijer J, Tanck MWT, Dobritzsch D, Zoetekouw L, Dekkers LL, Roelofsen J, Meinsma R, Wymenga M, Kulik W, Büchel B, Hennekam RCM, and Largiadèr CR
- Subjects
- Amino Acid Substitution, Dihydropyrimidine Dehydrogenase Deficiency blood, Female, HEK293 Cells, Humans, Middle Aged, Uracil blood, Codon, Nonsense, Dihydropyrimidine Dehydrogenase Deficiency genetics, Dihydrouracil Dehydrogenase (NADP) genetics, Haplotypes, Mutation, Missense, Polymorphism, Single Nucleotide
- Abstract
Dihydropyrimidine dehydrogenase (DPD) is the initial and rate-limiting enzyme in the catabolism of the pyrimidine bases uracil, thymine and the antineoplastic agent 5-fluorouracil. Genetic variations in the gene encoding DPD (DPYD) have emerged as predictive risk alleles for 5FU-associated toxicity. Here we report an in-depth analysis of genetic variants in DPYD and their consequences for DPD activity and pyrimidine metabolites in 100 Dutch healthy volunteers. 34 SNPs were detected in DPYD and 15 SNPs were associated with altered plasma concentrations of pyrimidine metabolites. DPD activity was significantly associated with the plasma concentrations of uracil, the presence of a specific DPYD mutation (c.1905+1G>A) and the combined presence of three risk variants in DPYD (c.1905+1G>A, c.1129-5923C>G, c.2846A>T), but not with an altered uracil/dihydrouracil (U/UH2) ratio. Various haplotypes were associated with different DPD activities (haplotype D3, a decreased DPD activity; haplotype F2, an increased DPD activity). Functional analysis of eight recombinant mutant DPD enzymes showed a reduced DPD activity, ranging from 35% to 84% of the wild-type enzyme. Analysis of a DPD homology model indicated that the structural effect of the novel p.G401R mutation is most likely minor. The clinical relevance of the p.D949V mutation was demonstrated in a cancer patient heterozygous for the c.2846A>T mutation and a novel nonsense mutation c.1681C>T (p.R561X), experiencing severe grade IV toxicity. Our studies showed that the endogenous levels of uracil and the U/UH2 ratio are poor predictors of an impaired DPD activity. Loading studies with uracil to identify patients with a DPD deficiency warrants further investigation., (Copyright © 2016 Elsevier B.V. All rights reserved.)
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- 2016
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47. High prevalence of hereditary thrombotic thrombocytopenic purpura in central Norway: from clinical observation to evidence.
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von Krogh AS, Quist-Paulsen P, Waage A, Langseth ØO, Thorstensen K, Brudevold R, Tjønnfjord GE, Largiadèr CR, Lämmle B, and Kremer Hovinga JA
- Subjects
- Adolescent, Adult, Aged, Alleles, Child, Child, Preschool, Cross-Sectional Studies, Family Health, Female, Gene Frequency, Geography, Homozygote, Humans, Infant, Infant, Newborn, Male, Middle Aged, Mutation, Norway epidemiology, Prevalence, Purpura, Thrombotic Thrombocytopenic genetics, Young Adult, ADAMTS13 Protein genetics, Purpura, Thrombotic Thrombocytopenic epidemiology
- Abstract
Unlabelled: Essentials The population prevalence of hereditary thrombotic thrombocytopenic purpura (TTP) is unknown. We studied the prevalence of hereditary TTP and population frequencies of two ADAMTS-13 mutations. A high frequency of hereditary TTP related to ADAMTS-13 mutation c.4143_4144dupA was found. Vicinity of ABO blood group and ADAMTS-13 loci may facilitate screening of ADAMTS-13 mutations., Summary: Background Hereditary thrombotic thrombocytopenic purpura (TTP) caused by ADAMTS-13 mutations is a rare, but serious condition. The prevalence is unknown, but it seems to be high in Norway. Objectives To identify all patients with hereditary TTP in central Norway and to investigate the prevalence of hereditary TTP and the population frequencies of two common ADAMTS-13 mutations. Patients/Methods Patients were identified in a cross-sectional study within the Central Norway Health Region by means of three different search strategies. Frequencies of ADAMTS-13 mutations, c.4143_4144dupA and c.3178 C>T (p.R1060W), were investigated in a population-based cohort (500 alleles) and in healthy blood donors (2104 alleles) by taking advantage of the close neighborhood of the ADAMTS-13 and ABO blood group gene loci. The observed prevalence of hereditary TTP was compared with the rates of ADAMTS-13 mutation carriers in different geographical regions. Results We identified 11 families with hereditary TTP in central Norway during the 10-year study period. The prevalence of hereditary TTP in central Norway was 16.7 × 10(-6) persons. The most prevalent mutation was c.4143_4144dupA, accounting for two-thirds of disease causing alleles among patients and having an allelic frequency of 0.33% in the central, 0.10% in the western, and 0.04% in the southeastern Norwegian population. The allelic frequency of c.3178 C>T (p.R1060W) in the population was even higher (0.3-1%), but this mutation was infrequent among patients, with no homozygous cases. Conclusions We found a high prevalence of hereditary TTP in central Norway and an apparently different penetrance of ADAMTS-13 mutations., (© 2015 International Society on Thrombosis and Haemostasis.)
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- 2016
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48. Influence of CYP3A5 genetic variation on everolimus maintenance dosing after cardiac transplantation.
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Lesche D, Sigurdardottir V, Setoud R, Englberger L, Fiedler GM, Largiadèr CR, Mohacsi P, and Sistonen J
- Subjects
- Adolescent, Adult, Aged, Dose-Response Relationship, Drug, Female, Follow-Up Studies, Graft Rejection drug therapy, Graft Survival, Humans, Immunosuppressive Agents administration & dosage, Maintenance Chemotherapy, Male, Middle Aged, Pilot Projects, Postoperative Complications, Prognosis, Risk Factors, Young Adult, Cytochrome P-450 CYP3A genetics, Everolimus administration & dosage, Graft Rejection genetics, Heart Transplantation adverse effects, Polymorphism, Genetic genetics
- Abstract
Background: Everolimus (ERL) has become an alternative to calcineurin inhibitors (CNIs) due to its renal-sparing properties, especially in heart transplant (HTx) recipients with kidney dysfunction. However, ERL dosing is challenging due to its narrow therapeutic window combined with high interindividual pharmacokinetic variability. Our aim was to evaluate the effect of clinical and genetic factors on ERL dosing in a pilot cohort of 37 HTx recipients., Methods: Variants in CYP3A5, CYP3A4, CYP2C8, POR, NR1I2, and ABCB1 were genotyped, and clinical data were retrieved from patient charts., Results: While ERL trough concentration (C0 ) was within the targeted range for most patients, over 30-fold variability in the dose-adjusted ERL C0 was observed. Regression analysis revealed a significant effect of the non-functional CYP3A5*3 variant on the dose-adjusted ERL C0 (p = 0.031). ERL dose requirement was 0.02 mg/kg/d higher in patients with CYP3A5*1/*3 genotype compared to patients with CYP3A5*3/*3 to reach the targeted C0 (p = 0.041). ERL therapy substantially improved estimated glomerular filtration rate (28.6 ± 6.6 mL/min/1.73 m(2)) in patients with baseline kidney dysfunction., Conclusion: Everolimus pharmacokinetics in HTx recipients is highly variable. Our preliminary data on patients on a CNI-free therapy regimen suggest that CYP3A5 genetic variation may contribute to this variability., (© 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)
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- 2015
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49. Clinical relevance of DPYD variants c.1679T>G, c.1236G>A/HapB3, and c.1601G>A as predictors of severe fluoropyrimidine-associated toxicity: a systematic review and meta-analysis of individual patient data.
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Meulendijks D, Henricks LM, Sonke GS, Deenen MJ, Froehlich TK, Amstutz U, Largiadèr CR, Jennings BA, Marinaki AM, Sanderson JD, Kleibl Z, Kleiblova P, Schwab M, Zanger UM, Palles C, Tomlinson I, Gross E, van Kuilenburg AB, Punt CJ, Koopman M, Beijnen JH, Cats A, and Schellens JH
- Subjects
- Capecitabine adverse effects, Capecitabine pharmacokinetics, Dihydrouracil Dehydrogenase (NADP) metabolism, Fluorouracil adverse effects, Fluorouracil pharmacokinetics, Gastrointestinal Diseases chemically induced, Gastrointestinal Diseases diagnosis, Genetic Predisposition to Disease, Hematologic Diseases chemically induced, Hematologic Diseases diagnosis, Humans, Multivariate Analysis, Neoplasms diagnosis, Neoplasms genetics, Odds Ratio, Pharmacogenetics, Phenotype, Risk Assessment, Risk Factors, Severity of Illness Index, Tegafur adverse effects, Tegafur pharmacokinetics, Antimetabolites, Antineoplastic adverse effects, Antimetabolites, Antineoplastic pharmacokinetics, Dihydrouracil Dehydrogenase (NADP) genetics, Gastrointestinal Diseases genetics, Hematologic Diseases genetics, Neoplasms drug therapy, Polymorphism, Genetic
- Abstract
Background: The best-known cause of intolerance to fluoropyrimidines is dihydropyrimidine dehydrogenase (DPD) deficiency, which can result from deleterious polymorphisms in the gene encoding DPD (DPYD), including DPYD*2A and c.2846A>T. Three other variants-DPYD c.1679T>G, c.1236G>A/HapB3, and c.1601G>A-have been associated with DPD deficiency, but no definitive evidence for the clinical validity of these variants is available. The primary objective of this systematic review and meta-analysis was to assess the clinical validity of c.1679T>G, c.1236G>A/HapB3, and c.1601G>A as predictors of severe fluoropyrimidine-associated toxicity., Methods: We did a systematic review of the literature published before Dec 17, 2014, to identify cohort studies investigating associations between DPYD c.1679T>G, c.1236G>A/HapB3, and c.1601G>A and severe (grade ≥3) fluoropyrimidine-associated toxicity in patients treated with fluoropyrimidines (fluorouracil, capecitabine, or tegafur-uracil as single agents, in combination with other anticancer drugs, or with radiotherapy). Individual patient data were retrieved and analysed in a multivariable analysis to obtain an adjusted relative risk (RR). Effect estimates were pooled by use of a random-effects meta-analysis. The threshold for significance was set at a p value of less than 0·0167 (Bonferroni correction)., Findings: 7365 patients from eight studies were included in the meta-analysis. DPYD c.1679T>G was significantly associated with fluoropyrimidine-associated toxicity (adjusted RR 4·40, 95% CI 2·08-9·30, p<0·0001), as was c.1236G>A/HapB3 (1·59, 1·29-1·97, p<0·0001). The association between c.1601G>A and fluoropyrimidine-associated toxicity was not significant (adjusted RR 1·52, 95% CI 0·86-2·70, p=0·15). Analysis of individual types of toxicity showed consistent associations of c.1679T>G and c.1236G>A/HapB3 with gastrointestinal toxicity (adjusted RR 5·72, 95% CI 1·40-23·33, p=0·015; and 2·04, 1·49-2·78, p<0·0001, respectively) and haematological toxicity (adjusted RR 9·76, 95% CI 3·03-31·48, p=0·00014; and 2·07, 1·17-3·68, p=0·013, respectively), but not with hand-foot syndrome. DPYD*2A and c.2846A>T were also significantly associated with severe fluoropyrimidine-associated toxicity (adjusted RR 2·85, 95% CI 1·75-4·62, p<0·0001; and 3·02, 2·22-4·10, p<0·0001, respectively)., Interpretation: DPYD variants c.1679T>G and c.1236G>A/HapB3 are clinically relevant predictors of fluoropyrimidine-associated toxicity. Upfront screening for these variants, in addition to the established variants DPYD*2A and c.2846A>T, is recommended to improve the safety of patients with cancer treated with fluoropyrimidines., Funding: None., (Copyright © 2015 Elsevier Ltd. All rights reserved.)
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- 2015
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50. Polymorphisms in MIR27A Associated with Early-Onset Toxicity in Fluoropyrimidine-Based Chemotherapy.
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Amstutz U, Offer SM, Sistonen J, Joerger M, Diasio RB, and Largiadèr CR
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- Adolescent, Adult, Aged, Aged, 80 and over, Female, Humans, Male, Middle Aged, Neoplasms genetics, Reverse Transcriptase Polymerase Chain Reaction, Young Adult, Antineoplastic Agents adverse effects, Dihydrouracil Dehydrogenase (NADP) genetics, Fluorouracil adverse effects, MicroRNAs genetics, Neoplasms drug therapy, Polymorphism, Single Nucleotide
- Abstract
Purpose: The microRNA miR-27a was recently shown to directly regulate dihydropyrimidine dehydrogenase (DPD), the key enzyme in fluoropyrimidine catabolism. A common polymorphism (rs895819A>G) in the miR-27a genomic region (MIR27A) was associated with reduced DPD activity in healthy volunteers, but the clinical relevance of this effect is still unknown. Here, we assessed the association of MIR27A germline variants with early-onset fluoropyrimidine toxicity., Experimental Design: MIR27A was sequenced in 514 patients with cancer receiving fluoropyrimidine-based chemotherapy. Associations of MIR27A polymorphisms with early-onset (cycles 1-2) fluoropyrimidine toxicity were assessed in the context of known risk variants in the DPD gene (DPYD) and additional covariates associated with toxicity., Results: The association of rs895819A>G with early-onset fluoropyrimidine toxicity was strongly dependent on DPYD risk variant carrier status (Pinteraction = 0.0025). In patients carrying DPYD risk variants, rs895819G was associated with a strongly increased toxicity risk [OR, 7.6; 95% confidence interval (CI), 1.7-34.7; P = 0.0085]. Overall, 71% (12/17) of patients who carried both rs895819G and a DPYD risk variant experienced severe toxicity. In patients without DPYD risk variants, rs895819G was associated with a modest decrease in toxicity risk (OR, 0.62; 95% CI, 0.43-0.9; P = 0.012)., Conclusions: These results indicate that miR-27a and rs895819A>G may be clinically relevant for further toxicity risk stratification in carriers of DPYD risk variants. Our data suggest that direct suppression of DPD by miR-27a is primarily relevant in the context of fluoropyrimidine toxicity in patients with reduced DPD activity. However, miR-27a regulation of additional targets may outweigh its effect on DPD in patients without DPYD risk variants., (©2015 American Association for Cancer Research.)
- Published
- 2015
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