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1.
Cell ; 156(1-2): 343-58, 2014 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-24439387

RESUMEN

Genome-wide association studies have revealed numerous risk loci associated with diverse diseases. However, identification of disease-causing variants within association loci remains a major challenge. Divergence in gene expression due to cis-regulatory variants in noncoding regions is central to disease susceptibility. We show that integrative computational analysis of phylogenetic conservation with a complexity assessment of co-occurring transcription factor binding sites (TFBS) can identify cis-regulatory variants and elucidate their mechanistic role in disease. Analysis of established type 2 diabetes risk loci revealed a striking clustering of distinct homeobox TFBS. We identified the PRRX1 homeobox factor as a repressor of PPARG2 expression in adipose cells and demonstrate its adverse effect on lipid metabolism and systemic insulin sensitivity, dependent on the rs4684847 risk allele that triggers PRRX1 binding. Thus, cross-species conservation analysis at the level of co-occurring TFBS provides a valuable contribution to the translation of genetic association signals to disease-related molecular mechanisms.


Asunto(s)
Diabetes Mellitus Tipo 2/genética , Polimorfismo de Nucleótido Simple , Animales , Línea Celular , Células Cultivadas , Secuencia Conservada , Regulación de la Expresión Génica , Estudio de Asociación del Genoma Completo , Proteínas de Homeodominio/metabolismo , Humanos , Resistencia a la Insulina , PPAR gamma/genética , Secuencias Reguladoras de Ácidos Nucleicos , Factores de Transcripción/metabolismo
2.
PLoS Comput Biol ; 20(7): e1011198, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38959284

RESUMEN

Interpreting transcriptome data is an important yet challenging aspect of bioinformatic analysis. While gene set enrichment analysis is a standard tool for interpreting regulatory changes, we utilize deep learning techniques, specifically autoencoder architectures, to learn latent variables that drive transcriptome signals. We investigate whether simple, variational autoencoder (VAE), and beta-weighted VAE are capable of learning reduced representations of transcriptomes that retain critical biological information. We propose a novel VAE that utilizes priors from biological data to direct the network to learn a representation of the transcriptome that is based on understandable biological concepts. After benchmarking five different autoencoder architectures, we found that each succeeded in reducing the transcriptomes to 50 latent dimensions, which captured enough variation for accurate reconstruction. The simple, fully connected autoencoder, performs best across the benchmarks, but lacks the characteristic of having directly interpretable latent dimensions. The beta-weighted, prior-informed VAE implementation is able to solve the benchmarking tasks, and provide semantically accurate latent features equating to biological pathways. This study opens a new direction for differential pathway analysis in transcriptomics with increased transparency and interpretability.


Asunto(s)
Biología Computacional , Aprendizaje Profundo , Perfilación de la Expresión Génica , Transcriptoma , Transcriptoma/genética , Biología Computacional/métodos , Perfilación de la Expresión Génica/métodos , Humanos , Algoritmos
3.
Lung ; 202(2): 157-170, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38494528

RESUMEN

PURPOSE: To investigate the transcriptome of human bronchial epithelial cells (HBEC) in response to serum from patients with different degrees of inflammation. METHODS: Serum from 19 COVID-19 patients obtained from the Hannover Unified Biobank was used. At the time of sampling, 5 patients had a WHO Clinical Progression Scale (WHO-CPS) score of 9 (severe illness). The remaining 14 patients had a WHO-CPS of below 9 (range 1-7), and lower illness. Multiplex immunoassay was used to assess serum inflammatory markers. The culture medium of HBEC was supplemented with 2% of the patient's serum, and the cells were cultured at 37 °C, 5% CO2 for 18 h. Subsequently, cellular RNA was used for RNA-Seq. RESULTS: Patients with scores below 9 had significantly lower albumin and serum levels of E-selectin, IL-8, and MCP-1 than patients with scores of 9. Principal component analysis based on 500 "core genes" of RNA-seq segregated cells into two subsets: exposed to serum from 4 (I) and 15 (II) patients. Cells from a subset (I) treated with serum from 4 patients with a score of 9 showed 5566 differentially expressed genes of which 2793 were up- and 2773 downregulated in comparison with cells of subset II treated with serum from 14 patients with scores between 1 and 7 and one with score = 9. In subset I cells, a higher expression of TLR4 and CXCL8 but a lower CDH1, ACE2, and HMOX1, and greater effects on genes involved in metabolic regulation, cytoskeletal organization, and kinase activity pathways were observed. CONCLUSION: This simple model could be useful to characterize patient serum and epithelial cell properties.


Asunto(s)
Inflamación , Transcriptoma , Humanos , Inflamación/genética , Inflamación/metabolismo , Células Epiteliales/metabolismo , Biomarcadores/metabolismo
4.
Gesundheitswesen ; 2024 Aug 22.
Artículo en Alemán | MEDLINE | ID: mdl-39173676

RESUMEN

In the early phase of the COVID-19 pandemic, many local collections of clinical data on patients infected with SARS-CoV-2 were initiated in Germany. As part of the National Pandemic Cohort Network (NAPKON) of the University Medicine Network, the "Integration Core" was established to design the legal, technical and organisational requirements for the integration of inventory data into ongoing prospective data collections and to test the feasibility of the newly developed solutions using use cases (UCs). Detailed study documents of the data collections were obtained. After structured document analysis, a review board evaluated the integrability of the data in NAPKON according to defined criteria. Of 30 university hospitals contacted, 20 responded to the request. Patient information and consent showed a heterogeneous picture with regard to the pseudonymised transfer of data to third parties and re-contact. The majority of the data collections (n=13) met the criteria for integration into NAPKON; four studies would require adjustments to the regulatory documents. Three cohorts were not suitable for inclusion in NAPKON. The legal framework for retrospective data integration and consent-free data use via research clauses (§27 BDSG) was elaborated by a legal opinion by TMF - Technology, Methods and Infrastructure for Networked Medical Research, Berlin. Two UCs selected by the NAPKON steering committee (CORKUM, LMU Munich; Pa-COVID-19, Charité- Universitätsmedizin Berlin) were used to demonstrate the feasibility of data integration in NAPKON by the end of 2021. Quality assurance and performance-based reimbursement of the cases were carried out according to the specifications. Based on the results, recommendations can be formulated for various contexts in order to create technical-operational prerequisites such as interoperability, interfaces and data models for data integration and to fulfil regulatory requirements on ethics, data protection, medical confidentiality and data access when integrating existing cohort data. The possible integration of data into research networks and their secondary use should be taken into account as early as the planning phase of a study - particularly with regard to informed consent - in order to maximise the benefits of the data collected.

5.
Clin Genet ; 104(2): 174-185, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37157876

RESUMEN

Wilson's disease (WD, MIM#277900) is an autosomal recessive disorder resulting in copper excess caused by biallelic variants in the ATP7B gene (MIM#606882) encoding a copper transporting P-type ATPase. ATP7B variants of unknown significance (VUS) are detected frequently, sometimes impeding a clear diagnosis. Functional analyses can help to classify these variants as benign or pathogenic. Additionally, variants already classified as (likely) pathogenic benefit from functional analyses to understand their pathomechanism, thus contribute to the development of personalized treatment approaches in the future. We described clinical features of six WD patients and functionally characterized five ATP7B missense variants (two VUS, three yet uncharacterized likely pathogenic variants), detected in these patients. We determined the protein level, copper export capacity, and cellular localization in an in vitro model and potential structural consequences using an ATP7B protein model based on AlphaFold. Our analyses give insight into the pathomechanism and allowed reclassification for the two VUS to likely pathogenic and for two of the three likely pathogenic variants to pathogenic.


Asunto(s)
ATPasas Transportadoras de Cobre , Degeneración Hepatolenticular , Humanos , Cobre , ATPasas Transportadoras de Cobre/genética , Degeneración Hepatolenticular/diagnóstico , Degeneración Hepatolenticular/genética , Mutación Missense/genética
6.
BMC Med Ethics ; 24(1): 84, 2023 10 17.
Artículo en Inglés | MEDLINE | ID: mdl-37848886

RESUMEN

With the outbreak of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), global researchers were confronted with major challenges. The German National Pandemic Cohort Network (NAPKON) was launched in fall 2020 to effectively leverage resources and bundle research activities in the fight against the coronavirus disease 2019 (COVID-19) pandemic. We analyzed the setup phase of NAPKON as an example for multicenter studies in Germany, highlighting challenges and optimization potential in connecting 59 university and nonuniversity study sites. We examined the ethics application process of 121 ethics submissions considering durations, annotations, and outcomes. Study site activation and recruitment processes were investigated and related to the incidence of SARS-CoV-2 infections. For all initial ethics applications, the median time to a positive ethics vote was less than two weeks and 30 of these study sites (65%) joined NAPKON within less than three weeks each. Electronic instead of postal ethics submission (9.5 days (Q1: 5.75, Q3: 17) vs. 14 days (Q1: 11, Q3: 26), p value = 0.01) and adoption of the primary ethics vote significantly accelerated the ethics application process. Each study center enrolled a median of 37 patients during the 14-month observation period, with large differences depending on the health sector. We found a positive correlation between recruitment performance and COVID-19 incidence as well as hospitalization incidence. Our analysis highlighted the challenges and opportunities of the federated system in Germany. Digital ethics application tools, adoption of a primary ethics vote and standardized formal requirements lead to harmonized and thus faster study initiation processes during a pandemic.


Asunto(s)
COVID-19 , Humanos , COVID-19/epidemiología , SARS-CoV-2 , Pandemias , Estudios de Cohortes , Alemania/epidemiología
7.
J Clin Immunol ; 42(5): 1083-1092, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35486341

RESUMEN

Inborn errors of immunity (IEI) are genetically driven disorders. With the advancement of sequencing technologies, a rapidly increasing number of gene defects has been identified, thereby mirroring the high heterogeneity in immunological and clinical presentations observed in patients. However, for a large majority of patients, no causative single nucleotide variant (SNV) or small indel can be identified using next-generation sequencing. First studies have shown that also copy number variants (CNVs) can cause IEI. Unfortunately, CNVs are not well examined in many routine diagnostic settings and the aim of this study was to assess the number of clinically relevant chromosomal losses and gains in a large cohort. We identified a total of 20 CNVs using whole exome sequencing data of a cohort of 191 patients with a suspected IEI. A definite molecular diagnosis could be made in five patients (2.6%), including pathogenic deletions affecting ICOS, TNFAIP3, and 22q11.2. CNVs of uncertain significance were observed in fifteen patients (7.9%), including deletions of 11q22.1q22.3 and 16p11.2 but also duplications affecting entire or parts of genes previously associated with IEI. Importantly, five patients carrying a CNV of uncertain significance also carried pathogenic or likely pathogenic SNVs (PIK3R1, NFKB1, NLRC4, DOCK2), or SNVs of unknown significance (NFKB2). This cooccurrence of SNVs and CNVs suggests modifying effects in some patients, and functional follow-up is warranted now in order to better understand phenotypic heterogeneity. In summary, the diagnostic yield of IEI can be increased substantially by evaluating CNVs, which allows an improved therapeutic management in those patients.


Asunto(s)
Aberraciones Cromosómicas , Variaciones en el Número de Copia de ADN , Enfermedades del Sistema Inmune , Estudios de Cohortes , Enfermedades Genéticas Congénitas , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Enfermedades del Sistema Inmune/genética , Secuenciación del Exoma
8.
Cancer Cell Int ; 22(1): 192, 2022 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-35578240

RESUMEN

BACKGROUND: In hepatocellular carcinoma (HCC), histone deacetylases (HDACs) are frequently overexpressed. This results in chromatin compaction and silencing of tumor-relevant genes and microRNAs. Modulation of microRNA expression is a potential treatment option for HCC. Therefore, we aimed to characterize the epigenetically regulated miR-129-5p regarding its functional effects and target genes to understand its relevance for HCC tumorigenesis. METHODS: Global miRNA expression of HCC cell lines (HLE, HLF, Huh7, HepG2, Hep3B) and normal liver cell lines (THLE-2, THLE-3) was analyzed after HDAC inhibition by miRNA sequencing. An in vivo xenograft mouse model and in vitro assays were used to investigate tumor-relevant functional effects following miR-129-5p transfection of HCC cells. To validate hepatoma-derived growth factor (HDGF) as a direct target gene of miR-129-5p, luciferase reporter assays were performed. Survival data and HDGF expression were analyzed in public HCC datasets. After siRNA-mediated knockdown of HDGF, its cancer-related functions were examined. RESULTS: HDAC inhibition induced the expression of miR-129-5p. Transfection of miR-129-5p increased the apoptosis of HCC cells, decreased proliferation, migration and ERK signaling in vitro and inhibited tumor growth in vivo. Direct binding of miR-129-5p to the 3'UTR of HDGF via a noncanonical binding site was validated by luciferase reporter assays. HDGF knockdown reduced cell viability and migration and increased apoptosis in Wnt-inactive HCC cells. These in vitro results were in line with the analysis of public HCC datasets showing that HDGF overexpression correlated with a worse survival prognosis, primarily in Wnt-inactive HCCs. CONCLUSIONS: This study provides detailed insights into the regulatory network of the tumor-suppressive, epigenetically regulated miR-129-5p in HCC. Our results reveal for the first time that the therapeutic application of mir-129-5p may have significant implications for the personalized treatment of patients with Wnt-inactive, advanced HCC by directly regulating HDGF. Therefore, miR-129-5p is a promising candidate for a microRNA replacement therapy to prevent HCC progression and tumor metastasis.

9.
Respir Res ; 23(1): 343, 2022 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-36514048

RESUMEN

BACKGROUND: SARS-CoV-2 infected patients show heterogeneous clinical presentations ranging from mild symptoms to severe respiratory failure and death. Consequently, various markers reflect this wide spectrum of disease presentations. METHODS: Our pilot cohort included moderate (n = 10) and severe (n = 10) COVID-19 patients, and 10 healthy controls. We determined plasma levels of nine acute phase proteins (APPs) by nephelometry, and full-length (M65), caspase-cleaved (M30) cytokeratin 18, and ADAMTS13 (a disintegrin-like and metalloprotease with thrombospondin type-1 motif 13) by ELISA. In addition, we examined whole plasma N-glycosylation by capillary gel electrophoresis coupled to laser-induced fluorescence detection (CGE-LIF). RESULTS: When compared to controls, COVID-19 patients had significantly lower concentrations of ADAMTS13 and albumin (ALB) but higher M30, M65, α1-acid glycoprotein (AGP), α1-antitrypsin (AAT), ceruloplasmin (CP), haptoglobin (HP), and high-sensitivity C-reactive protein (hs-CRP). The concentrations of α1-antichymotrypsin (ACT), α2-macroglobulin (A2MG) and serum amyloid A (SAA) proteins did not differ. We found significantly higher levels of AAT and M65 but lower ALB in severe compared to moderate COVID-19 patients. N-glycan analysis of the serum proteome revealed increased levels of oligomannose- and sialylated di-antennary glycans and decreased non-sialylated di-antennary glycan A2G2 in COVID-19 patients compared to controls. CONCLUSIONS: COVID-19-associated changes in levels and N-glycosylation of specific plasma proteins highlight complexity of inflammatory process and grant further investigations.


Asunto(s)
COVID-19 , Humanos , Proteínas de Fase Aguda/análisis , COVID-19/diagnóstico , Proyectos Piloto , Polisacáridos , SARS-CoV-2
10.
Int J Mol Sci ; 23(9)2022 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-35563522

RESUMEN

Chromosomal instability (CIN) can be a driver of tumorigenesis but is also a promising therapeutic target for cancer associated with poor prognosis such as triple negative breast cancer (TNBC). The treatment of TNBC cells with defects in DNA repair genes with poly(ADP-ribose) polymerase inhibitor (PARPi) massively increases CIN, resulting in apoptosis. Here, we identified a previously unknown role of microRNA-449a in CIN. The transfection of TNBC cell lines HCC38, HCC1937 and HCC1395 with microRNA-449a mimics led to induced apoptosis, reduced cell proliferation, and reduced expression of genes in homology directed repair (HDR) in microarray analyses. EME1 was identified as a new target gene by immunoprecipitation and luciferase assays. The reduced expression of EME1 led to an increased frequency of ultrafine bridges, 53BP1 foci, and micronuclei. The induced expression of microRNA-449a elevated CIN beyond tolerable levels and induced apoptosis in TNBC cell lines by two different mechanisms: (I) promoting chromatid mis-segregation by targeting endonuclease EME1 and (II) inhibiting HDR by downregulating key players of the HDR network such as E2F3, BIRC5, BRCA2 and RAD51. The ectopic expression of microRNA-449a enhanced the toxic effect of PARPi in cells with pathogenic germline BRCA1 variants. The newly identified role makes microRNA-449a an interesting therapeutic target for TNBC.


Asunto(s)
Antineoplásicos , MicroARNs , Neoplasias de la Mama Triple Negativas , Antineoplásicos/farmacología , Línea Celular Tumoral , Cromátides/metabolismo , Reparación del ADN/genética , Regulación Neoplásica de la Expresión Génica , Humanos , MicroARNs/metabolismo , Inhibidores de Poli(ADP-Ribosa) Polimerasas/farmacología , Inhibidores de Poli(ADP-Ribosa) Polimerasas/uso terapéutico , Neoplasias de la Mama Triple Negativas/patología
11.
Genes Chromosomes Cancer ; 60(11): 733-742, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34296808

RESUMEN

Among the different breast cancer subtypes, triple-negative breast cancer (TNBC) is associated with a poor prognosis, low survival rates, and high expression of histone deacetylases. Treatment with histone deacetylase inhibitor trichostatin A (TSA) leads to an increased expression of potential tumor-suppressive miRNAs. Characterization of these miRNAs can help to find new molecular targets for treatment of TNBC. We identified differentially expressed miRNAs by microarray analyses after treatment with TSA in the TNBC cell lines HCC38, HCC1395, and HCC1935. The gene locus of hsa-miRNA-192-5p (miR-192) and hsa-miR-194-2 (miR-194-2) with its host gene, long noncoding RNA miR-194-2HG, has been linked to inhibition of migration in different tumor types. Therefore, we examined tumor-relevant functional effects using WST-1-based proliferation, capsase-3/7-based apoptosis, and trans-well migration assays after transfection with miRNA mimics or specific siRNAs. We demonstrated the tumor-suppressive capacity of miR-192 in TNBC cells, which was exerted through inhibition of proliferation, induction of apoptosis, and reduction of migration. Gene expression and bioinformatics analyses of TNBC cell lines transfected with miR-192 mimics, identified a number of genes involved in migration including the Rho GTPase Activating Protein ARHGAP19. Through RNA immunoprecipitation we demonstrated the direct binding of miR-192 and ARHGAP19. Downregulation of ARHGAP19 expression by either miR-192 or siRNA inhibited migration of TNBC cells significantly. Our findings demonstrate that overexpression of epigenetically deregulated miR-192 decreases proliferation, promotes apoptosis, and inhibits migration of TNBC cell lines.


Asunto(s)
Proteínas Activadoras de GTPasa/genética , MicroARNs/genética , Neoplasias de la Mama Triple Negativas/genética , Línea Celular , Movimiento Celular , Regulación hacia Abajo , Proteínas Activadoras de GTPasa/metabolismo , Regulación Neoplásica de la Expresión Génica , Humanos , MicroARNs/metabolismo , Neoplasias de la Mama Triple Negativas/metabolismo
12.
Genes Chromosomes Cancer ; 60(6): 452-457, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33486841

RESUMEN

A complex karyotype, detected in myelodysplastic syndrome (MDS) and acute myeloid leukaemia (AML), is associated with a reduced median survival. The most frequent chromosomal aberrations in complex karyotypes are deletions of 5q and 17p harboring the tumor suppressor gene TP53. The unbalanced translocation der(5;17) involving chromosome 5q and 17p is a recurrent aberration in MDS/AML, resulting in TP53 loss. We analyzed the karyotypes of 178 patients with an unbalanced translocation der(5;17) using fluorescence R-/G-banding analysis. Whenever possible, fluorescence in situ hybridization (FISH) (n = 138/141), multicolor FISH (n = 8), telomere length measurement (n = 9), targeted DNA sequencing (n = 13), array-CGH (n = 7) and targeted RNA sequencing (n = 2) were conducted. The der(5;17) aberration was accompanied with loss of genetic material in 7q (53%), -7 (27%), gain of 21q (29%), +8 (17%) and - 18 (16%) and all analyzed patients (n = 13) showed a (likely) pathogenic variant inTP53. The der(5;17) cohort showed significantly shortened telomeres in comparison to the healthy age-matched controls (P < .05), but there was no significant telomere shortening in comparison to MDS/AML patients with a complex karyotype without der(5;17). No fusion genes resulted from the unbalanced translocation. This study demonstrates that the unbalanced translocation der(5;17) is associated with a biallelic inactivation of TP53 due to a deletion of TP53 in one allele and a pathogenic variant of the second TP53 allele. Since the breakpoints are located within (near-) heterochromatic regions, alterations of DNA methylation or histone modifications may be involved in the generation of der(5;17).


Asunto(s)
Cromosomas Humanos Par 17/genética , Cromosomas Humanos Par 5/genética , Leucemia Mieloide Aguda/genética , Síndromes Mielodisplásicos/genética , Translocación Genética , Proteína p53 Supresora de Tumor/genética , Cariotipo Anormal , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Femenino , Humanos , Leucemia Mieloide Aguda/patología , Masculino , Persona de Mediana Edad , Síndromes Mielodisplásicos/patología
13.
Hum Mol Genet ; 28(8): 1381-1391, 2019 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-30629177

RESUMEN

The effect of mitochondrial DNA (mtDNA) variation on peripheral blood transcriptomics in health and disease is not fully known. Sex-specific mitochondrially controlled gene expression patterns have been shown in Drosophila melanogaster but in humans, evidence is lacking. Functional variation in mtDNA may also have a role in the development of type 2 diabetes and its precursor state, i.e. prediabetes. We examined the associations between mitochondrial single-nucleotide polymorphisms (mtSNPs) and peripheral blood transcriptomics with a focus on sex- and prediabetes-specific effects. The genome-wide blood cell expression data of 19 637 probes, 199 deep-sequenced mtSNPs and nine haplogroups of 955 individuals from a population-based Young Finns Study cohort were used. Significant associations were identified with linear regression and analysis of covariance. The effects of sex and prediabetes on the associations between gene expression and mtSNPs were studied using random-effect meta-analysis. Our analysis identified 53 significant expression probe-mtSNP associations after Bonferroni correction, involving 7 genes and 31 mtSNPs. Eight probe-mtSNP signals remained independent after conditional analysis. In addition, five genes showed differential expression between haplogroups. The meta-analysis did not show any significant differences in linear model effect sizes between males and females but identified the association between the OASL gene and mtSNP C16294T to show prediabetes-specific effects. This study pinpoints new independent mtSNPs associated with peripheral blood transcriptomics and replicates six previously reported associations, providing further evidence of the mitochondrial genetic control of blood cell gene expression. In addition, we present evidence that prediabetes might lead to perturbations in mitochondrial control.


Asunto(s)
ADN Mitocondrial/genética , Regulación de la Expresión Génica/genética , Adulto , Secuencia de Bases , Células Sanguíneas/metabolismo , Células Sanguíneas/fisiología , ADN Mitocondrial/sangre , Diabetes Mellitus Tipo 2/genética , Femenino , Expresión Génica , Estudios de Asociación Genética/métodos , Variación Genética/genética , Genética de Población/métodos , Estudio de Asociación del Genoma Completo/métodos , Haplotipos , Humanos , Masculino , Persona de Mediana Edad , Mitocondrias/genética , Polimorfismo de Nucleótido Simple/genética , Análisis de Secuencia de ADN , Transcriptoma/genética
14.
BMC Bioinformatics ; 21(1): 28, 2020 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-31992182

RESUMEN

BACKGROUND: Despite the significant contribution of transcriptomics to the fields of biological and biomedical research, interpreting long lists of significantly differentially expressed genes remains a challenging step in the analysis process. Gene set enrichment analysis is a standard approach for summarizing differentially expressed genes into pathways or other gene groupings. Here, we explore an alternative approach to utilizing gene sets from curated databases. We examine the method of deriving custom gene sets which may be relevant to a given experiment using reference data sets from previous transcriptomics studies. We call these data-derived gene sets, "gene signatures" for the biological process tested in the previous study. We focus on the feasibility of this approach in analyzing immune-related processes, which are complicated in their nature but play an important role in the medical research. RESULTS: We evaluate several statistical approaches to detecting the activity of a gene signature in a target data set. We compare the performance of the data-derived gene signature approach with comparable GO term gene sets across all of the statistical tests. A total of 61 differential expression comparisons generated from 26 transcriptome experiments were included in the analysis. These experiments covered eight immunological processes in eight types of leukocytes. The data-derived signatures were used to detect the presence of immunological processes in the test data with modest accuracy (AUC = 0.67). The performance for GO and literature based gene sets was worse (AUC = 0.59). Both approaches were plagued by poor specificity. CONCLUSIONS: When investigators seek to test specific hypotheses, the data-derived signature approach can perform as well, if not better than standard gene-set based approaches for immunological signatures. Furthermore, the data-derived signatures can be generated in the cases that well-defined gene sets are lacking from pathway databases and also offer the opportunity for defining signatures in a cell-type specific manner. However, neither the data-derived signatures nor standard gene-sets can be demonstrated to reliably provide negative predictions for negative cases. We conclude that the data-derived signature approach is a useful and sometimes necessary tool, but analysts should be weary of false positives.


Asunto(s)
Perfilación de la Expresión Génica , Leucocitos/metabolismo , Animales , Curaduría de Datos , Bases de Datos Genéticas , Humanos , Leucocitos/inmunología , Ratones , Sensibilidad y Especificidad
15.
Ann Hum Genet ; 84(2): 195-200, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31596515

RESUMEN

Wilson's disease is an autosomal recessive disorder resulting from copper excess. Some patients with clinical Wilson's disease symptoms exhibit no or only heterozygous pathogenic variants in the coding region of the disease-causing ATP7B gene. Therefore, the ATP7B promoter region is of special interest. Metal-responsive elements (MREs) located in the ATP7B promoter are promising motifs in modulating the ATP7B expression. We studied protein interaction of MREe, MREc, and MREd by electrophoretic mobility shift assays and revealed specific interactions for all MREs. We further narrowed down the specific binding site. Proteins potentially binding to the three MREs were identified by MatInspector analyses. Metal regulatory transcription factor 1 (MTF1) could be validated to bind to MREe by electrophoretic mobility shift assays. ATP7B promoter-driven reporter gene expression was significantly increased because of this interaction. MTF1 is a strong candidate in regulating the ATP7B expression through MREe binding.


Asunto(s)
Carcinoma Hepatocelular/metabolismo , ATPasas Transportadoras de Cobre/genética , Proteínas de Unión al ADN/metabolismo , Regulación Neoplásica de la Expresión Génica , Neoplasias Hepáticas/metabolismo , Regiones Promotoras Genéticas , Elementos de Respuesta , Factores de Transcripción/metabolismo , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patología , ATPasas Transportadoras de Cobre/metabolismo , Proteínas de Unión al ADN/genética , Células Hep G2 , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patología , Metales/metabolismo , Factores de Transcripción/genética , Factor de Transcripción MTF-1
16.
Int J Cancer ; 144(11): 2683-2694, 2019 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-30426508

RESUMEN

NGS-based multiple gene panel resequencing in combination with a high resolution CGH-array was used to identify genetic risk factors for hereditary breast and/or ovarian cancer in 237 high risk patients who were previously tested negative for pathogenic BRCA1/2 variants. All patients were screened for pathogenic variants in 94 different cancer predisposing genes. We identified 32 pathogenic variants in 14 different genes (ATM, BLM, BRCA1, CDH1, CHEK2, FANCG, FANCM, FH, HRAS, PALB2, PMS2, PTEN, RAD51C and NBN) in 30 patients (12.7%). Two pathogenic BRCA1 variants that were previously undetected due to less comprehensive and sensitive methods were found. Five pathogenic variants are novel, three of which occur in genes yet unrelated to hereditary breast and/or ovarian cancer (FANCG, FH and HRAS). In our cohort we discovered a remarkably high frequency of truncating variants in FANCM (2.1%), which has recently been suggested as a susceptibility gene for hereditary breast cancer. Two patients of our cohort carried two different pathogenic variants each and 10 other patients in whom a pathogenic variant was confirmed also harbored a variant of unknown significance in a breast and ovarian cancer susceptibility gene. We were able to identify pathogenic variants predisposing for tumor formation in 12.3% of BRCA1/2 negative breast and/or ovarian cancer patients.


Asunto(s)
Neoplasias de la Mama Masculina/genética , Neoplasias de la Mama/genética , ADN Helicasas/genética , Síndrome de Cáncer de Mama y Ovario Hereditario/genética , Neoplasias Ováricas/genética , Adolescente , Adulto , Anciano , Proteína BRCA1/genética , Proteína BRCA2/genética , Neoplasias de la Mama/patología , Estudios de Cohortes , Análisis Mutacional de ADN , Femenino , Pruebas Genéticas , Humanos , Masculino , Anamnesis , Persona de Mediana Edad , Adulto Joven
17.
J Transl Med ; 17(1): 365, 2019 11 11.
Artículo en Inglés | MEDLINE | ID: mdl-31711507

RESUMEN

BACKGROUND: There continues to be a great need for better biomarkers and host-directed treatment targets for community-acquired pneumonia (CAP). Alterations in phospholipid metabolism may constitute a source of small molecule biomarkers for acute infections including CAP. Evidence from animal models of pulmonary infections and sepsis suggests that inhibiting acid sphingomyelinase (which releases ceramides from sphingomyelins) may reduce end-organ damage. METHODS: We measured concentrations of 105 phospholipids, 40 acylcarnitines, and 4 ceramides, as well as acid sphingomyelinase activity, in plasma from patients with CAP (n = 29, sampled on admission and 4 subsequent time points), chronic obstructive pulmonary disease exacerbation with infection (COPD, n = 13) as a clinically important disease control, and 33 age- and sex-matched controls. RESULTS: Phospholipid concentrations were greatly decreased in CAP and normalized along clinical improvement. Greatest changes were seen in phosphatidylcholines, followed by lysophosphatidylcholines, sphingomyelins and ceramides (three of which were upregulated), and were least in acylcarnitines. Changes in COPD were less pronounced, but also differed qualitatively, e.g. by increases in selected sphingomyelins. We identified highly accurate biomarkers for CAP (AUC ≤ 0.97) and COPD (AUC ≤ 0.93) vs. Controls, and moderately accurate biomarkers for CAP vs. COPD (AUC ≤ 0.83), all of which were phospholipids. Phosphatidylcholines, lysophosphatidylcholines, and sphingomyelins were also markedly decreased in S. aureus-infected human A549 and differentiated THP1 cells. Correlations with C-reactive protein and procalcitonin were predominantly negative but only of mild-to-moderate extent, suggesting that these markers reflect more than merely inflammation. Consistent with the increased ceramide concentrations, increased acid sphingomyelinase activity accurately distinguished CAP (fold change = 2.8, AUC = 0.94) and COPD (1.75, 0.88) from Controls and normalized with clinical resolution. CONCLUSIONS: The results underscore the high potential of plasma phospholipids as biomarkers for CAP, begin to reveal differences in lipid dysregulation between CAP and infection-associated COPD exacerbation, and suggest that the decreases in plasma concentrations are at least partially determined by changes in host target cells. Furthermore, they provide validation in clinical blood samples of acid sphingomyelinase as a potential treatment target to improve clinical outcome of CAP.


Asunto(s)
Fosfolípidos/sangre , Neumonía/sangre , Esfingomielina Fosfodiesterasa/sangre , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores/sangre , Estudios de Casos y Controles , Ceramidas/sangre , Infecciones Comunitarias Adquiridas/sangre , Infecciones Comunitarias Adquiridas/diagnóstico , Femenino , Humanos , Mediadores de Inflamación/sangre , Lipidómica , Masculino , Persona de Mediana Edad , Neumonía/diagnóstico , Estudios Prospectivos , Enfermedad Pulmonar Obstructiva Crónica/sangre , Enfermedad Pulmonar Obstructiva Crónica/diagnóstico , Investigación Biomédica Traslacional , Adulto Joven
18.
PLoS Biol ; 14(8): e1002521, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27483445

RESUMEN

Modern approaches for research with human biospecimens employ a variety of substantially different types of ethics approval and informed consent. In most cases, standard ethics reporting such as "consent and approval was obtained" is no longer meaningful. A structured analysis of 120 biospecimen studies recently published in top journals revealed that more than 85% reported on consent and approval, but in more than 90% of cases, this reporting was insufficient and thus potentially misleading. Editorial policies, reporting guidelines, and material transfer agreements should include recommendations for meaningful ethics reporting in biospecimen research. Meaningful ethics reporting is possible without higher word counts and could support public trust as well as networked research.


Asunto(s)
Bancos de Muestras Biológicas/ética , Investigación Genética/ética , Consentimiento Informado/ética , Bancos de Muestras Biológicas/normas , Políticas Editoriales , Humanos , Consentimiento Informado/normas , Edición/ética , Edición/normas , Informe de Investigación/normas , Confianza
19.
BMC Infect Dis ; 19(1): 656, 2019 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-31337344

RESUMEN

BACKGROUND: The immune response to seasonal influenza vaccines decreases with advancing age. Therefore, an adjuvanted inactivated trivalent influenza vaccine (Fluad®) exists for elderly individuals. Fluad® is more immunogenic and efficacious than conventional influenza vaccines. However, the immune response varies and may still result in high frequencies of poor responders. Therefore, we aimed to a) examine the prevalence of a weak response to Fluad® and b) identify potential risk factors. METHODS: A prospective population-based study among individuals 65-80 years old was conducted in 2015/2016 in Hannover, Germany (n = 200). Hemagglutination-inhibition titers 21 days after vaccination with Fluad® served as indicator of vaccine responsiveness. RESULTS: The percentage of vaccinees with an inadequate vaccine response varied depending on the influenza strain: it was lowest for H3N2 (13.5%; 95% CI, 9.4-18.9%), intermediate for B strain (37.0%; 30.6-43.9%), and highest for H1N1 (49.0%; 42.2-55.9%). The risk of a weak response to the influenza A H1N1 strain was independently associated with self-reported diabetes (AOR, 4.64; 95% CI, 1.16-18.54), a history of herpes zoster (2.27; 1.01-5.10) and, to a much lesser extent, increasing age (change per year, 1.08; 0.99-1.16). In addition, herpes zoster was the only risk factor for a weak response to the H3N2 antigen (AOR, 3.12; 1.18-8.23). We found no significant association between sex, Body Mass Index, cancer, hypertension, heart attack and CMV seropositivity and a weak response to these two influenza A antigens. Despite its occurence in over one third of vaccinees, none of the variables examined proved to be risk factors for a weak response to the B antigen. CONCLUSIONS: A considerable proportion of elderly individuals displayed a weak vaccine response to this adjuvanted seasonal influenza vaccine and further efforts are thus needed to improve immune responses to influenza vaccination among the elderly. Diabetes and herpes zoster were identified as potentially modifiable risk factors for a poor vaccine response against influenza A antigens, but the results also reveal the need for broader investigations to identify risk factors for inadequate responses to influenza B antigens. TRIAL REGISTRATION: No. NCT02362919 (ClinicalTrials.gov, date of registration: 09.02.2015).


Asunto(s)
Diabetes Mellitus/inmunología , Herpes Zóster/inmunología , Inmunidad Humoral , Vacunas contra la Influenza/inmunología , Adyuvantes Inmunológicos/farmacología , Anciano , Anciano de 80 o más Años , Antígenos Virales/inmunología , Femenino , Alemania , Humanos , Subtipo H1N1 del Virus de la Influenza A/inmunología , Subtipo H3N2 del Virus de la Influenza A/inmunología , Vacunas contra la Influenza/efectos adversos , Vacunas contra la Influenza/farmacología , Gripe Humana/inmunología , Gripe Humana/prevención & control , Masculino , Estudios Prospectivos , Estaciones del Año , Autoinforme
20.
BMC Pulm Med ; 19(1): 238, 2019 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-31818288

RESUMEN

BACKGROUND: Pediatric community acquired pneumonia (pedCAP) is one of the leading causes for childhood morbidity accounting for up to 20% of pediatric hospital admissions in high income countries. In spite of its high morbidity, updated epidemiological and pathogen data after introduction of preventive vaccination and novel pathogen screening strategies are limited. Moreover, there is a need for validated recommendations on diagnostic and treatment regimens in pedCAP. Through collection of patient data and analysis of pathogen and host factors in a large sample of unselected pedCAP patients in Germany, we aim to address and substantially improve this situation. METHODS: pedCAPNETZ is an observational, multi-center study on pedCAP. Thus far, nine study centers in hospitals, outpatient clinics and practices have been initiated and more than 400 patients with radiologically confirmed pneumonia have been enrolled, aiming at a total of 1000 study participants. Employing an online data base, information on disease course, treatment as well as demographical and socioeconomical data is recorded. Patients are followed up until day 90 after enrollment; Comprehensive biosample collection and a central pedCAPNETZ biobank allow for in-depth analyses of pathogen and host factors. Standardized workflows to assure sample logistics and data management in more than fifteen future study centers have been established. DISCUSSION: Through comprehensive epidemiological, clinical and biological analyses, pedCAPNETZ fills an important gap in pediatric and infection research. To secure dissemination of the registry, we will raise clinical and scientific awareness at all levels. We aim at participating in decision making processes for guidelines and prevention strategies. Ultimately, we hope the results of the pedCAPNETZ registry will help to improve care and quality of life in pedCAP patients in the future.


Asunto(s)
Infecciones Comunitarias Adquiridas/epidemiología , Hospitalización , Neumonía Bacteriana/epidemiología , Adolescente , Niño , Preescolar , Bases de Datos Factuales , Progresión de la Enfermedad , Alemania/epidemiología , Humanos , Estudios Prospectivos , Proyectos de Investigación , Sepsis/etiología , Índice de Severidad de la Enfermedad
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