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1.
Clin Exp Dermatol ; 49(8): 801-809, 2024 Jul 19.
Article in English | MEDLINE | ID: mdl-38240024

ABSTRACT

BACKGROUND: Secukinumab, an anti-interleukin (IL)-17A monoclonal antibody, induces histological and molecular resolution of psoriatic plaques by 12 weeks. However, the long-term effects of secukinumab on the molecular resolution of psoriatic inflammation remain unknown. OBJECTIVES: To investigate the molecular resolution of psoriasis following 52 weeks of secukinumab treatment. METHODS: This was a two-part phase II randomized double-blinded placebo-controlled 52-week study of patients with moderate-to-severe psoriasis receiving secukinumab 300 mg (NCT01537432). Psoriatic lesional and nonlesional skin biopsies were obtained at baseline and at weeks 12 and 52, and the composition of the residual disease genomic profile (RDGP; i.e. 'molecular scar') of biopsies from secukinumab responders analysed. RESULTS: After 52 weeks of treatment, 14 of 24 enrolled patients were considered to be clinical responders [≥ 75% improvement in Psoriasis Area and Severity Index (PASI 75)], 4 of 24 were considered to be nonresponders (< PASI 75) and 6 of 24 patients were lost to follow-up; both the histological and transcriptomic profiles of PASI 75 responders improved from week 12 to week 52. RDGP transcripts of histological responders only partially overlapped between weeks 12 and 52, despite a similar number of transcripts in each RDGP; specifically, four novel transcript subsets showed distinct expression dynamics between weeks 12 and 52 ('slow-resolving', 'recurring', 'persistent' and 'resolved'), with anti-inflammatory and immunomodulatory genes (e.g. SOCS1, CD207 and IL37) notably restored at week 52. Shorter disease duration prior to secukinumab treatment coincided with greater transcript improvements at weeks 12 and 52. CONCLUSIONS: Secukinumab improves the histological and molecular phenotype of psoriatic lesional skin up to 52 weeks of treatment; these results suggest possible mechanisms that drive long-term control of psoriasis.


Subject(s)
Antibodies, Monoclonal, Humanized , Interleukin-17 , Psoriasis , Transcriptome , Humans , Psoriasis/drug therapy , Psoriasis/genetics , Psoriasis/pathology , Antibodies, Monoclonal, Humanized/therapeutic use , Interleukin-17/metabolism , Interleukin-17/antagonists & inhibitors , Double-Blind Method , Male , Female , Adult , Middle Aged , Antibodies, Monoclonal/therapeutic use , Severity of Illness Index , Biomarkers/metabolism , Skin/pathology , Skin/metabolism , Treatment Outcome
2.
Epilepsy Behav ; 150: 109572, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38070406

ABSTRACT

RATIONALE: Seizure induction techniques are used in the epilepsy monitoring unit (EMU) to increase diagnostic yield and reduce length of stay. There are insufficient data on the efficacy of alcohol as an induction technique. METHODS: We performed a retrospective cohort study using six years of EMU data at our institution. We compared cases who received alcohol for seizure induction to matched controls who did not. The groups were matched on the following variables: age, reason for admission, length of stay, number of antiseizure medications (ASM) at admission, whether ASMs were tapered during admission, and presence of interictal epileptiform discharges. We used both propensity score and exact matching strategies. We compared the likelihood of epileptic seizures and nonepileptic events in cases versus controls using Kaplan-Meier time-to-event analysis, as well as odds ratios for these outcomes occurring at any time during the admission. RESULTS: We analyzed 256 cases who received alcohol (median dose 2.5 standard drinks) and 256 propensity score-matched controls. Cases who received alcohol were no more likely than controls to have an epileptic seizure (X2(1) = 0.01, p = 0.93) or nonepileptic event (X2(1) = 2.1, p = 0.14) in the first 48 h after alcohol administration. For the admission overall, cases were no more likely to have an epileptic seizure (OR 0.89, 95 % CI 0.61-1.28, p = 0.58), nonepileptic event (OR 0.97, CI 0.62-1.53, p = 1.00), nor require rescue benzodiazepine (OR 0.63, CI 0.35-1.12, p = 0.15). Stratified analyses revealed no increased risk of epileptic seizure in any subgroups. Sensitivity analysis using exact matching showed that results were robust to matching strategy. CONCLUSIONS: Alcohol was not an effective induction technique in the EMU. This finding has implications for counseling patients with epilepsy about the risks of drinking alcohol in moderation in their daily lives.


Subject(s)
Electroencephalography , Epilepsy , Humans , Retrospective Studies , Electroencephalography/methods , Seizures/psychology , Epilepsy/complications , Epilepsy/diagnosis , Epilepsy/epidemiology , Monitoring, Physiologic , Ethanol/therapeutic use
3.
J Clin Neurosci ; 119: 76-84, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37988976

ABSTRACT

BACKGROUND: Increased morbidity in many patients with myasthenia gravis (MG) on long-term immunosuppression highlights the need for improved treatments. The aim of this study is to investigate the safety and efficacy of iscalimab (CFZ533), a fully human anti-CD40 monoclonal antibody, in patients with moderate-to-severe MG receiving standard-of-care (SoC) therapies. METHODS: In this double-blind, placebo-controlled phase 2 study, symptomatic patients (n = 44) despite SoC were randomized 1:1 to receive intravenous iscalimab (10 mg/kg; n = 22) or placebo (n = 22) every 4 weeks for 6 doses in total. Patients were followed up for 6 months after the last dose. The total duration of the study was 52 weeks. RESULTS: In total, 34 of 44 patients (77.3 %) completed the study. The primary endpoint, Quantitative MG score, did not change significantly between baseline and week 25 for iscalimab (median [90 % CI], -4.07 [-5.67, -2.47]) versus placebo (-2.93 [-4.53, -1.33]); however, non-thymectomized patients (n = 29) showed more favorable results (iscalimab, -4.35 [-6.07, -2.64] vs placebo, -2.26 [-4.16, -0.36]). A statistically significant difference between iscalimab and placebo groups was observed in MG Composite score (adjusted mean change: -4.19 [-6.67, -1.72]; p = 0.007) at week 13, and MG-Activities of Daily Living score (-1.93 [-3.24, -0.62]; p = 0.018) at week 21. Adverse events were comparable between the iscalimab (91 %) and placebo (96 %) groups. CONCLUSION: Iscalimab showed favorable safety and improvements compared with placebo in non-thymectomized patients with moderate-to-severe MG. It did not show any protective effect in patients with moderate-to-severe MG.


Subject(s)
Activities of Daily Living , Myasthenia Gravis , Humans , Treatment Outcome , Antibodies, Monoclonal/adverse effects , Myasthenia Gravis/drug therapy , Myasthenia Gravis/chemically induced , Double-Blind Method
4.
Am J Hum Genet ; 110(10): 1817-1824, 2023 10 05.
Article in English | MEDLINE | ID: mdl-37659414

ABSTRACT

Response to the anti-IL17 monoclonal antibody secukinumab is heterogeneous, and not all participants respond to treatment. Understanding whether this heterogeneity is driven by genetic variation is a key aim of pharmacogenetics and could influence precision medicine approaches in inflammatory diseases. Using changes in disease activity scores across 5,218 genotyped individuals from 19 clinical trials across four indications (psoriatic arthritis, psoriasis, ankylosing spondylitis, and rheumatoid arthritis), we tested whether genetics predicted response to secukinumab. We did not find any evidence of association between treatment response and common variants, imputed HLA alleles, polygenic risk scores of disease susceptibility, or cross-disease components of shared genetic risk. This suggests that anti-IL17 therapy is equally effective regardless of an individual's genetic background, a finding that has important implications for future genetic studies of biological therapy response in inflammatory diseases.


Subject(s)
Arthritis, Psoriatic , Arthritis, Rheumatoid , Psoriasis , Humans , Arthritis, Psoriatic/drug therapy , Arthritis, Psoriatic/genetics , Psoriasis/drug therapy , Psoriasis/genetics , Arthritis, Rheumatoid/drug therapy , Arthritis, Rheumatoid/genetics , Genotype
5.
Epilepsia ; 64(3): 754-768, 2023 03.
Article in English | MEDLINE | ID: mdl-36484572

ABSTRACT

OBJECTIVE: Interictal spikes help localize seizure generators as part of surgical planning for drug-resistant epilepsy. However, there are often multiple spike populations whose frequencies change over time, influenced by brain state. Understanding state changes in spike rates will improve our ability to use spikes for surgical planning. Our goal was to determine the effect of sleep and seizures on interictal spikes, and to use sleep and seizure-related changes in spikes to localize the seizure-onset zone (SOZ). METHODS: We performed a retrospective analysis of intracranial electroencephalography (EEG) data from patients with focal epilepsy. We automatically detected interictal spikes and we classified different time periods as awake or asleep based on the ratio of alpha to delta power, with a secondary analysis using the recently published SleepSEEG algorithm. We analyzed spike rates surrounding sleep and seizures. We developed a model to localize the SOZ using state-dependent spike rates. RESULTS: We analyzed data from 101 patients (54 women, age range 16-69). The normalized alpha-delta power ratio accurately classified wake from sleep periods (area under the curve = .90). Spikes were more frequent in sleep than wakefulness and in the post-ictal compared to the pre-ictal state. Patients with temporal lobe epilepsy had a greater wake-to-sleep and pre- to post-ictal spike rate increase compared to patients with extra-temporal epilepsy. A machine-learning classifier incorporating state-dependent spike rates accurately identified the SOZ (area under the curve = .83). Spike rates tended to be higher and better localize the seizure-onset zone in non-rapid eye movement (NREM) sleep than in wake or REM sleep. SIGNIFICANCE: The change in spike rates surrounding sleep and seizures differs between temporal and extra-temporal lobe epilepsy. Spikes are more frequent and better localize the SOZ in sleep, particularly in NREM sleep. Quantitative analysis of spikes may provide useful ancillary data to localize the SOZ and improve surgical planning.


Subject(s)
Epilepsies, Partial , Epilepsy, Temporal Lobe , Epilepsy , Humans , Female , Adolescent , Young Adult , Adult , Middle Aged , Aged , Retrospective Studies , Seizures/surgery , Epilepsy/surgery , Sleep , Electroencephalography
7.
Cancers (Basel) ; 13(12)2021 Jun 10.
Article in English | MEDLINE | ID: mdl-34200741

ABSTRACT

Patients with cancer, both hematologic and solid malignancies, are at increased risk for thrombosis and thromboembolism. In addition to general risk factors such as immobility and major surgery, shared by non-cancer patients, cancer patients are exposed to specific thrombotic risk factors. These include, among other factors, cancer-induced hypercoagulation, and chemotherapy-mediated endothelial dysfunction as well as tumor-cell-derived microparticles. After an episode of thrombosis in a cancer patient, secondary thromboprophylaxis to prevent recurrent thromboembolism has long been established and is typically continued as long as the cancer is active or actively treated. On the other hand, primary prophylaxis, even though firmly established in hospitalized cancer patients, has only recently been studied in ambulatory patients. This recent change is mostly due to the emergence of direct oral anticoagulants (DOACs). DOACs have a shorter half-life than vitamin K antagonists (VKA), and they overcome the need for parenteral application, the latter of which is associated with low-molecular-weight heparins (LMWH) and can be difficult for the patient to endure in the long term. Here, first, we discuss the clinical trials of primary thromboprophylaxis in the population of cancer patients in general, including the use of VKA, LMWH, and DOACs, and the potential drug interactions with pre-existing medications that need to be taken into account. Second, we focus on special situations in cancer patients where primary prophylactic anticoagulation should be considered, including myeloma, major surgery, indwelling catheters, or immobilization, concomitant diseases such as renal insufficiency, liver disease, or thrombophilia, as well as situations with a high bleeding risk, particularly thrombocytopenia, and specific drugs that may require primary thromboprophylaxis. We provide a novel algorithm intended to aid specialists but also family practitioners and nurses who care for cancer patients in the decision process of primary thromboprophylaxis in the individual patient.

8.
J Allergy Clin Immunol Pract ; 8(9): 3121-3127.e1, 2020 10.
Article in English | MEDLINE | ID: mdl-32422371

ABSTRACT

BACKGROUND: Little is known about the epidemiology of advanced systemic mastocytosis (advSM). OBJECTIVES: To investigate epidemiologic features and diagnostic pitfalls of advSM in Germany. METHODS: Therefore, 140 patients from a single German reference center of the European Competence Network on Mastocytosis between 2003 and 2018 were analyzed. RESULTS: The patients' median age was 68 years (range, 26-86 years), and male versus female ratio was 2:1. An elevated serum tryptase, a KIT D816 mutation, and additional somatic mutations, for example, in SRSF2, ASXL1, or RUNX1, were identified in 95%, 91%, and 74% of patients, respectively. Median overall survival was 3.5 years (range, 0.03-14.3 years; male vs female 2.6 vs 4.2 years; P = .02). Two categories of misdiagnoses were identified in 51 of 140 (36%) patients: First, systemic mastocytosis (SM) was overlooked in 28 of 140 (20%) patients primarily diagnosed with various subtypes of myeloid neoplasms. Second, 23 of 140 (16%) patients were diagnosed with supposed progression from indolent SM to advSM; however, combination of an elevated KIT D816V variant allele frequency in peripheral blood (n = 22), monocytosis (n = 9), eosinophilia (n = 6), and/or mutations in SRSF2, ASXL1, or RUNX1 (n = 10) suggest that distinct signs of potential advSM were overlooked in virtually all patients. Based on locally diagnosed patients in an area of 2.5 million inhabitants, but obviously without considering more, yet unrecognized cases, the incidence and prevalence of advSM is at least 0.8 and 5.2, respectively, per 1 million inhabitants. CONCLUSIONS: Adequate analyses of tryptase levels, bone marrow morphology, and genetics in patients with myeloid neoplasms or SM would help to prevent the significant underdiagnosis of advSM.


Subject(s)
Mastocytosis, Systemic , Mastocytosis , Aged , Bone Marrow , Female , Germany , Humans , Male , Mastocytosis, Systemic/diagnosis , Mastocytosis, Systemic/epidemiology , Mastocytosis, Systemic/genetics , Mutation , Proto-Oncogene Proteins c-kit/genetics
9.
J Allergy Clin Immunol ; 144(3): 750-763, 2019 09.
Article in English | MEDLINE | ID: mdl-31129129

ABSTRACT

BACKGROUND: Hyperactivity of the IL-23/IL-17 axis is central to plaque psoriasis pathogenesis. Secukinumab, a fully human mAb that selectively inhibits IL-17A, is approved for treatment of psoriasis, psoriatic arthritis, and ankylosing spondylitis. Secukinumab improves the complete spectrum of psoriasis manifestations, with durable clinical responses beyond 5 years of treatment. In the feed-forward model of plaque chronicity, IL-17A has been hypothesized as the key driver of pathogenic gene expression by lesional keratinocytes, but in vivo evidence in human subjects is lacking. METHODS: We performed a randomized, double-blind, placebo-controlled study (NCT01537432) of patients receiving secukinumab at the clinically approved dose up to 12 weeks. We then correlated plaque and nonlesional skin transcriptomic profiles with histopathologic and clinical measures of efficacy. RESULTS: After 12 weeks of treatment, secukinumab reversed plaque histopathology in the majority of patients and modulated thousands of transcripts. Suppression of the IL-23/IL-17 axis by secukinumab was evident at week 1 and continued through week 12, including reductions in levels of the upstream cytokine IL-23, the drug target IL-17A, and downstream targets, including ß-defensin 2. Suppression of the IL-23/IL-17 axis by secukinumab at week 4 was associated with clinical and histologic responses at week 12. Secukinumab did not affect ex vivo T-cell activation, which is consistent with its favorable long-term safety profile. CONCLUSION: Our data suggest that IL-17A is the critical node within the multidimensional pathogenic immune circuits that maintain psoriasis plaques and that early reduction of IL-17A-dependent feed-forward transcripts synthesized by hyperplastic keratinocytes favors plaque resolution.


Subject(s)
Antibodies, Monoclonal, Humanized/therapeutic use , Interleukin-17/antagonists & inhibitors , Psoriasis/drug therapy , Antibodies, Monoclonal, Humanized/pharmacology , Double-Blind Method , Humans , Interleukin-23/antagonists & inhibitors , Psoriasis/genetics , Psoriasis/pathology , Skin/metabolism , Skin/pathology , Transcriptome/drug effects , Treatment Outcome
10.
Allergy ; 74(1): 141-151, 2019 01.
Article in English | MEDLINE | ID: mdl-29974963

ABSTRACT

BACKGROUND: Omalizumab, a humanized recombinant monoclonal anti-IgE antibody, proved to be effective in patients with chronic spontaneous urticaria (CSU), including severe and treatment-refractory CSU. Here, we report omalizumab's effect on gene expression in skin biopsies from CSU patients enrolled in a double-blind, placebo-controlled study. METHODS: Chronic spontaneous urticaria patients (18-75 years) were randomized to either 300 mg omalizumab (n = 20) or placebo (n = 10) administered s.c. every 4 weeks for 12 weeks (NCT01599637). Lesional and nonlesional skin biopsies were collected from the same area of consenting patients and assessed at baseline and on Day 85 compared with skin biopsies from the same area of 10 untreated healthy volunteers (HVs). Gene expression data were generated using Affymetrix HG-U133Plus2.0 microarrays. Statistical analyses were performed using R packages. RESULTS: At baseline, 63 transcripts were differentially expressed between lesional and nonlesional skin. Two-thirds of these lesional signatures were also differentially expressed between lesional and HV skin. Upon treatment with omalizumab, >75% of lesional signatures changed to reflect nonlesional skin expression levels (different vs placebo, P < 0.01). Transcripts upregulated in lesional skin (vs nonlesional and/or HV skin) suggested increased mast cell/leukocyte infiltration (FCER1G, C3AR1, CD93, S100A8, and S100A9), increased oxidative stress, vascularization (CYR61), and skin repair events (KRT6A, KRT16). Lesional signatures were not modulated by treatment in nonresponders (defined based on UAS7 longitudinal changes ≥16). CONCLUSION: Omalizumab, in treatment responders, reverted transcriptional signatures associated with CSU lesion phenotype to reflect nonlesional/HV expression levels; this is consistent with observed omalizumab-mediated clinical improvement observed in patients with CSU.


Subject(s)
Chronic Urticaria/drug therapy , Omalizumab/pharmacology , Transcriptome/drug effects , Adolescent , Adult , Aged , Anti-Allergic Agents/pharmacology , Biopsy , Chronic Urticaria/genetics , Double-Blind Method , Female , Humans , Male , Middle Aged , Omalizumab/therapeutic use , Skin/pathology , Treatment Outcome , Young Adult
11.
Ann Rheum Dis ; 76(1): 303-309, 2017 Jan.
Article in English | MEDLINE | ID: mdl-27474763

ABSTRACT

OBJECTIVE: To explore whether gene expression profiling can identify a molecular mechanism for the clinical benefit of canakinumab treatment in patents with tumour necrosis factor receptor-associated periodic syndrome (TRAPS). METHODS: Blood samples were collected from 20 patients with active TRAPS who received canakinumab 150 mg every 4 weeks for 4 months in an open-label proof-of-concept phase II study, and from 20 aged-matched healthy volunteers. Gene expression levels were evaluated in whole blood samples by microarray analysis for arrays passing quality control checks. RESULTS: Patients with TRAPS exhibited a gene expression signature in blood that differed from that in healthy volunteers. Upon treatment with canakinumab, many genes relevant to disease pathogenesis moved towards levels seen in the healthy volunteers. Canakinumab downregulated the TRAPS-causing gene (TNF super family receptor 1A (TNFRSF1A)), the drug-target gene (interleukin (IL)-1B) and other inflammation-related genes (eg, MAPK14). In addition, several inflammation-related pathways were evident among the differentially expressed genes. Canakinumab treatment reduced neutrophil counts, but the observed expression differences remained after correction for this. CONCLUSIONS: These gene expression data support a model in which canakinumab produces clinical benefit in TRAPS by increasing neutrophil apoptosis and reducing pro-inflammatory signals resulting from the inhibition of IL-1ß. Notably, treatment normalised the overexpression of TNFRSF1A, suggesting that canakinumab has a direct impact on the main pathogenic mechanism in TRAPS. TRIAL REGISTRATION NUMBER: NCT01242813.


Subject(s)
Antibodies, Monoclonal/pharmacology , Familial Mediterranean Fever/genetics , Gene Expression Regulation/drug effects , Receptors, Tumor Necrosis Factor/genetics , Adolescent , Adult , Aged , Antibodies, Monoclonal/administration & dosage , Antibodies, Monoclonal/therapeutic use , Antibodies, Monoclonal, Humanized , Child , Drug Administration Schedule , Familial Mediterranean Fever/drug therapy , Familial Mediterranean Fever/metabolism , Female , Gene Expression Profiling/methods , Genetic Predisposition to Disease , Humans , Interleukin-1beta/antagonists & inhibitors , Leukocyte Count , Male , Middle Aged , Neutrophils/drug effects , Receptors, Tumor Necrosis Factor/biosynthesis , Young Adult
12.
Eur J Paediatr Neurol ; 20(1): 11-9, 2016 Jan.
Article in English | MEDLINE | ID: mdl-26614551

ABSTRACT

BACKGROUND: The use of complementary and alternative medicine (CAM) is popular. Parents of children suffering from epilepsy may also consider administering CAM to their children. Systematic data about frequency of and motivations for CAM use, however, are scarce. METHODS: In a university hospital's neuropaediatric department parents of patients aged 0-18 years suffering from epilepsy were consecutively invited to take part in a structured interview during 4 months in 2014. RESULTS: Of the invited parents, 164/165 (99%) agreed to participate. From those, 21/164 (13%) stated that they used CAM in their child. The highest independent predictive value of CAM use was the occurrence of adverse drug events (ADE) of anticonvulsants as judged by parents. Patients affected by ADE had a 5.6 higher chance of receiving CAM compared to patients without ADE. Most commonly used were homeopathy (14/21, 67%) and osteopathy (12/21, 57%). The internet was the most frequently used source of information (14/21, 67%). Of the parents, 10/21 (48%) described positive effects of CAM on seizure frequency, 12/21 (57%) on general condition of their child, and 20/21 (95%) wished to continue CAM for epilepsy therapy. From the non-users of CAM, 91/143 (66%) expressed the desire to learn more about CAM for epilepsy therapy. LIMITATIONS: Our study was performed in a university hospital in a large urban city in Eastern Germany. CAM user rates can differ in other parts of Germany and Europe, in other institutions and for chronic diseases other than epilepsy. CONCLUSION: The main reason for CAM use was the occurrence of ADE of anticonvulsants. More than half of the parents saw a benefit of CAM for their children. Almost all parents wished to continue CAM use, even those who did not see concrete positive effects.


Subject(s)
Complementary Therapies/statistics & numerical data , Epilepsy/therapy , Adolescent , Adult , Anticonvulsants/adverse effects , Child , Child, Preschool , Complementary Therapies/economics , Drug-Related Side Effects and Adverse Reactions/epidemiology , Epilepsy/economics , Epilepsy/epidemiology , Female , Germany/epidemiology , Homeopathy/statistics & numerical data , Humans , Infant , Infant, Newborn , Male , Osteopathic Medicine/statistics & numerical data , Parents , Patient Satisfaction , Physician-Patient Relations , Prevalence , Socioeconomic Factors , Surveys and Questionnaires
13.
J Cell Sci ; 128(6): 1217-29, 2015 Mar 15.
Article in English | MEDLINE | ID: mdl-25616894

ABSTRACT

A new cyclic decadepsipeptide was isolated from Chaetosphaeria tulasneorum with potent bioactivity on mammalian and yeast cells. Chemogenomic profiling in S. cerevisiae indicated that the Sec61 translocon complex, the machinery for protein translocation and membrane insertion at the endoplasmic reticulum, is the target. The profiles were similar to those of cyclic heptadepsipeptides of a distinct chemotype (including HUN-7293 and cotransin) that had previously been shown to inhibit cotranslational translocation at the mammalian Sec61 translocon. Unbiased, genome-wide mutagenesis followed by full-genome sequencing in both fungal and mammalian cells identified dominant mutations in Sec61p (yeast) or Sec61α1 (mammals) that conferred resistance. Most, but not all, of these mutations affected inhibition by both chemotypes, despite an absence of structural similarity. Biochemical analysis confirmed inhibition of protein translocation into the endoplasmic reticulum of both co- and post-translationally translocated substrates by both chemotypes, demonstrating a mechanism independent of a translating ribosome. Most interestingly, both chemotypes were found to also inhibit SecYEG, the bacterial Sec61 translocon homolog. We suggest 'decatransin' as the name for this new decadepsipeptide translocation inhibitor.


Subject(s)
Biological Products/pharmacology , Endoplasmic Reticulum/drug effects , Membrane Proteins/metabolism , Protein Transport/drug effects , Saccharomyces cerevisiae Proteins/metabolism , Saccharomyces cerevisiae/metabolism , Animals , Ascomycota/metabolism , COS Cells , Cells, Cultured , Chlorocebus aethiops , HCT116 Cells , Humans , Membrane Proteins/antagonists & inhibitors , Peptides, Cyclic/pharmacology , Polymorphism, Single Nucleotide/genetics , SEC Translocation Channels , Saccharomyces cerevisiae/genetics , Saccharomyces cerevisiae/growth & development
14.
Ann N Y Acad Sci ; 1333: 43-64, 2014 Dec.
Article in English | MEDLINE | ID: mdl-25424900

ABSTRACT

The class of adhesion G protein-coupled receptors (aGPCRs), with 33 human homologs, is the second largest family of GPCRs. In addition to a seven-transmembrane α-helix-a structural feature of all GPCRs-the class of aGPCRs is characterized by the presence of a large N-terminal extracellular region. In addition, all aGPCRs but one (GPR123) contain a GPCR autoproteolysis-inducing (GAIN) domain that mediates autoproteolytic cleavage at the GPCR autoproteolysis site motif to generate N- and a C-terminal fragments (NTF and CTF, respectively) during protein maturation. Subsequently, the NTF and CTF are associated noncovalently as a heterodimer at the plasma membrane. While the biological function of the GAIN domain-mediated autocleavage is not fully understood, mounting evidence suggests that the NTF and CTF possess distinct biological activities in addition to their function as a receptor unit. We discuss recent advances in understanding the biological functions, signaling mechanisms, and disease associations of the aGPCRs.


Subject(s)
Cell Adhesion , Receptors, G-Protein-Coupled/physiology , Animals , Developmental Disabilities/genetics , Humans , Mutation , Neoplasms/genetics , Signal Transduction , Synapses/physiology
15.
Biomark Res ; 2: 17, 2014.
Article in English | MEDLINE | ID: mdl-25285214

ABSTRACT

BACKGROUND: Exact sample annotation in expression microarray datasets is essential for any type of pharmacogenomics research. RESULTS: Candidate markers were explored through the application of Hartigans' dip test statistics to a publically available human whole genome microarray dataset. The marker performance was tested on 188 serial samples from 53 donors and of variable tissue origin from five public microarray datasets. A qualified transcript marker panel consisting of three probe sets for human leukocyte antigens HLA-DQA1 (2 probe sets) and HLA-DRB4 identified sample donor identifier inconsistencies in six of the 188 test samples. About 3% of the test samples require root-cause analysis due to unresolvable inaccuracies. CONCLUSIONS: The transcript marker panel consisting of HLA-DQA1 and HLA-DRB4 represents a robust, tissue-independent composite marker to assist control donor annotation concordance at the transcript level. Allele-selectivity of HLA genes renders them good candidates for "fingerprinting" with donor specific expression pattern.

16.
Nat Methods ; 11(8): 809-15, 2014 Aug.
Article in English | MEDLINE | ID: mdl-24973947

ABSTRACT

MicroRNAs are important negative regulators of protein-coding gene expression and have been studied intensively over the past years. Several measurement platforms have been developed to determine relative miRNA abundance in biological samples using different technologies such as small RNA sequencing, reverse transcription-quantitative PCR (RT-qPCR) and (microarray) hybridization. In this study, we systematically compared 12 commercially available platforms for analysis of microRNA expression. We measured an identical set of 20 standardized positive and negative control samples, including human universal reference RNA, human brain RNA and titrations thereof, human serum samples and synthetic spikes from microRNA family members with varying homology. We developed robust quality metrics to objectively assess platform performance in terms of reproducibility, sensitivity, accuracy, specificity and concordance of differential expression. The results indicate that each method has its strengths and weaknesses, which help to guide informed selection of a quantitative microRNA gene expression platform for particular study goals.


Subject(s)
MicroRNAs/genetics , Quality Control , Reproducibility of Results
17.
Clin Transl Med ; 3: 36, 2014.
Article in English | MEDLINE | ID: mdl-25984272

ABSTRACT

BACKGROUND: Clinically useful biomarkers for patient stratification and monitoring of disease progression and drug response are in big demand in drug development and for addressing potential safety concerns. Many diseases influence the frequency and phenotype of cells found in the peripheral blood and the transcriptome of blood cells. Changes in cell type composition influence whole blood gene expression analysis results and thus the discovery of true transcript level changes remains a challenge. We propose a robust and reproducible procedure, which includes whole transcriptome gene expression profiling of major subsets of immune cell cells directly sorted from whole blood. METHODS: Target cells were enriched using magnetic microbeads and an autoMACS® Pro Separator (Miltenyi Biotec). Flow cytometric analysis for purity was performed before and after magnetic cell sorting. Total RNA was hybridized on HGU133 Plus 2.0 expression microarrays (Affymetrix, USA). CEL files signal intensity values were condensed using RMA and a custom CDF file (EntrezGene-based). RESULTS: Positive selection by use of MACS® Technology coupled to transcriptomics was assessed for eight different peripheral blood cell types, CD14+ monocytes, CD3+, CD4+, or CD8+ T cells, CD15+ granulocytes, CD19+ B cells, CD56+ NK cells, and CD45+ pan leukocytes. RNA quality from enriched cells was above a RIN of eight. GeneChip analysis confirmed cell type specific transcriptome profiles. Storing whole blood collected in an EDTA Vacutainer® tube at 4°C followed by MACS does not activate sorted cells. Gene expression analysis supports cell enrichment measurements by MACS. CONCLUSIONS: The proposed workflow generates reproducible cell-type specific transcriptome data which can be translated to clinical settings and used to identify clinically relevant gene expression biomarkers from whole blood samples. This procedure enables the integration of transcriptomics of relevant immune cell subsets sorted directly from whole blood in clinical trial protocols.

18.
Microbiol Res ; 169(2-3): 107-20, 2014.
Article in English | MEDLINE | ID: mdl-24360837

ABSTRACT

Due to evolutionary conservation of biology, experimental knowledge captured from genetic studies in eukaryotic model organisms provides insight into human cellular pathways and ultimately physiology. Yeast chemogenomic profiling is a powerful approach for annotating cellular responses to small molecules. Using an optimized platform, we provide the relative sensitivities of the heterozygous and homozygous deletion collections for nearly 1800 biologically active compounds. The data quality enables unique insights into pathways that are sensitive and resistant to a given perturbation, as demonstrated with both known and novel compounds. We present examples of novel compounds that inhibit the therapeutically relevant fatty acid synthase and desaturase (Fas1p and Ole1p), and demonstrate how the individual profiles facilitate hypothesis-driven experiments to delineate compound mechanism of action. Importantly, the scale and diversity of tested compounds yields a dataset where the number of modulated pathways approaches saturation. This resource can be used to map novel biological connections, and also identify functions for unannotated genes. We validated hypotheses generated by global two-way hierarchical clustering of profiles for (i) novel compounds with a similar mechanism of action acting upon microtubules or vacuolar ATPases, and (ii) an un-annotated ORF, YIL060w, that plays a role in respiration in the mitochondria. Finally, we identify and characterize background mutations in the widely used yeast deletion collection which should improve the interpretation of past and future screens throughout the community. This comprehensive resource of cellular responses enables the expansion of our understanding of eukaryotic pathway biology.


Subject(s)
Saccharomyces cerevisiae Proteins/genetics , Saccharomyces cerevisiae/chemistry , Saccharomyces cerevisiae/genetics , Antifungal Agents/pharmacology , Biosynthetic Pathways , Drug Resistance, Fungal , Gene Expression Regulation, Fungal , High-Throughput Screening Assays , Molecular Sequence Data , Phylogeny , Saccharomyces cerevisiae/classification , Saccharomyces cerevisiae/drug effects , Saccharomyces cerevisiae Proteins/metabolism
19.
BMC Genomics ; 14: 644, 2013 Sep 23.
Article in English | MEDLINE | ID: mdl-24059264

ABSTRACT

BACKGROUND: Due to the unparalleled genetic diversity of its peoples, Africa is attracting growing research attention. Several African populations have been assessed in global initiatives such as the International HapMap and 1000 Genomes Projects. Notably excluded, however, is the southern Africa region, which is inhabited predominantly by southeastern Bantu-speakers, currently suffering under the dual burden of infectious and non-communicable diseases. Limited reference data for these individuals hampers medical research and prevents thorough understanding of the underlying population substructure. Here, we present the most detailed exploration, to date, of genetic diversity in 94 unrelated southeastern Bantu-speaking South Africans, resident in urban Soweto (Johannesburg). RESULTS: Participants were typed for ~4.3 million SNPs using the Illumina Omni5 beadchip. PCA and ADMIXTURE plots were used to compare the observed variation with that seen in selected populations worldwide. Results indicated that Sowetans, and other southeastern Bantu-speakers, are a clearly distinct group from other African populations previously investigated, reflecting a unique genetic history with small, but significant contributions from diverse sources. To assess the suitability of our sample as representative of Sowetans, we compared our results to participants in a larger rheumatoid arthritis case-control study. The control group showed good clustering with our sample, but among the cases were individuals who demonstrated notable admixture. CONCLUSIONS: Sowetan population structure appears unique compared to other black Africans, and may have clinical implications. Our data represent a suitable reference set for southeastern Bantu-speakers, on par with a HapMap type reference population, and constitute a prelude to the Southern African Human Genome Programme.


Subject(s)
Black People/genetics , Genetics, Population , Polymorphism, Single Nucleotide , Female , Genotyping Techniques , Humans , Male , Principal Component Analysis , South Africa
20.
Biomarkers ; 18(5): 436-45, 2013 Aug.
Article in English | MEDLINE | ID: mdl-23829492

ABSTRACT

CONTEXT: Correct gender assignment in humans at the molecular level is crucial in many scientific disciplines and applied areas. MATERIALS AND METHODS: Candidate gender markers were identified through supervised statistical analysis of genome wide microarray expression data from human blood samples (N = 123, 58 female, 65 male) as a training set. The potential of the markers to predict undisclosed tissue donor gender was tested on microarray data from 13 healthy and 11 cancerous human tissue collections (internal) and external datasets from samples of varying tissue origin. The abundance of some genes in the marker panel was quantified by RT-PCR as alternative analytical technology. RESULTS: We identified and qualified predictive, gender-specific transcript markers based on a set of five genes (RPS4Y1, EIF1AY, DDX3Y, KDM5D and XIST). CONCLUSION: Gene expression marker panels can be used as a robust tissue- and platform-independent predictive approach for gender determination.


Subject(s)
Gene Expression Profiling , RNA, Messenger/blood , Sex Determination Analysis/methods , Biomarkers/blood , DEAD-box RNA Helicases/blood , DEAD-box RNA Helicases/genetics , Female , Histone Demethylases/blood , Histone Demethylases/genetics , Humans , Male , Minor Histocompatibility Antigens , Oligonucleotide Array Sequence Analysis , Organ Specificity , RNA, Long Noncoding/blood , RNA, Long Noncoding/genetics , RNA, Messenger/genetics , Ribosomal Proteins/blood , Ribosomal Proteins/genetics , Transcriptome
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