21 research outputs found

    Flexible web-based integration of distributed large-scale human protein interaction maps

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    Protein-protein interactions constitute the backbone of many molecular processes. This has motivated the recent construction of several large-scale human protein-protein interaction maps [1-10]. Although these maps clearly offer a wealth of information, their use is challenging: complexity, rapid growth, and fragmentation of interaction data hamper their usability. To overcome these hurdles, we have developed a publicly accessible database termed UniHI (Unified Human Interactome) for integration of human protein-protein interaction data. This database is designed to provide biomedical researchers a common platform for exploring previously disconnected human interaction maps. UniHI offers researchers flexible integrated tools for accessing comprehensive information about the human interactome. Several features included in the UniHI allow users to perform various types of network-oriented and functional analysis. At present, UniHI contains over 160,000 distinct interactions between 17,000 unique proteins from ten major interaction maps derived by both computational and experimental approaches [1-10]. Here we describe the details of the implementation and maintenance of UniHI and discuss the challenges that have to be addressed for a successful integration of interaction data

    Sclerotiorin stabilizes the assembly of nonfibrillar Abeta42 oligomers with low toxicity, seeding activity, and beta-sheet content

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    The self-assembly of the 42-residue amyloid-β peptide, Aβ42, into fibrillar aggregates is associated with neuronal dysfunction and toxicity in Alzheimer's disease (AD) patient brains, suggesting that small molecules acting on this process might interfere with pathogenesis. Here, we present experimental evidence that the small molecule sclerotiorin (SCL), a natural product belonging to the group of azaphilones, potently delays both seeded and non-seeded Aβ42 polymerization in cell-free assays. Mechanistic biochemical studies revealed that the inhibitory effect of SCL on fibrillogenesis is caused by its ability to kinetically stabilize small Aβ42 oligomers. These structures exhibit low β-sheet content and do not possess seeding activity, indicating that SCL acts very early in the amyloid formation cascade before the assembly of seeding-competent, β-sheet-rich fibrillar aggregates. Investigations with NMR WaterLOGSY experiments confirmed the association of Aβ42 assemblies with SCL in solution. Furthermore, using ion mobility-mass spectrometry we observed that SCL directly interacts with a small fraction of Aβ42 monomers in the gas phase. In comparison to typical amyloid fibrils, small SCL-stabilized Aβ42 assemblies are inefficiently taken up into mammalian cells and have low toxicity in cell-based assays. Overall, these mechanistic studies support a pathological role of stable, β-sheet-rich Aβ42 fibrils in AD, while structures with low β-sheet content may be less relevant

    Impact of age on efficacy and toxicity of nilotinib in patients with chronic myeloid leukemia in chronic phase : ENEST1st subanalysis

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    Purpose Achievement of deep molecular response with a tyrosine kinase inhibitor in patients with chronic myeloid leukemia (CML) is required to attempt discontinuation of therapy in these patients. The current subanalysis from the Evaluating Nilotinib Efficacy and Safety in Clinical Trials as First-Line Treatment (ENEST1st) study evaluated whether age has an impact on the achievement of deeper molecular responses or safety with frontline nilotinib in patients with CML. Methods ENEST1st is an open-label, multicenter, single-arm, prospective study of nilotinib 300 mg twice daily in patients with newly diagnosed CML in chronic phase. The patients were stratified into the following 4 groups based on age: young (18-39 years), middle age (40-59 years), elderly (60-74 years), and old (>= 75 years). The primary end point was the rate of molecular response 4 ([MR4] BCR-ABL1 Results Of the 1091 patients enrolled, 1089 were considered in the analysis, of whom, 23% (n = 243), 45% (n = 494), 27% (n = 300), and 5% (n = 52) were categorized as young, middle age, elderly, and old, respectively. At 18 months, the rates of MR4 were 33.9% (95% confidence interval [CI], 27.8-40.0%) in the young, 39.6% (95% CI, 35.3-44.0%) in the middle-aged, 40.5% (95% CI, 34.8-46.1%) in the elderly, and 35.4% (95% CI, 21.9-48.9%) in the old patients. Although the incidence of adverse events was slightly different, no new specific safety signals were observed across the 4 age groups. Conclusions This subanalysis of the ENEST1st study showed that age did not have a relevant impact on the deep molecular response rates associated with nilotinib therapy in newly diagnosed patients with CML and eventually on the eligibility of the patients to attempt treatment discontinuation.Peer reviewe

    Chronic Myeloid Leukemia Patient's Voice About the Experience of Treatment-Free Remission Failure: Results From the Italian Sub-Study of ENESTPath Exploring the Emotional Experience of Patients During Different Phases of a Clinical Trial

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    Background: The main objective of this study is to gain further insights on how chronic myeloid leukemia (CML) patients involved in an interventional clinical trial with the purpose of reaching treatment free remission (TFR) phase, perceived and experienced TFR failure. TFR failure was defined for the individual patient as either not being eligible for drug discontinuation or as having relapse in the TFR phase with reintroduction of nilotinib treatment. Methods: Using a qualitative approach, out of 25 patients with CML who experienced TFR failure 14 were interviewed. Patients' views and experiences were explored using in-depth interviews, analyzed using the Interpretative Phenomenological Analysis (IPA). Results: The analysis of the interviews revealed that the experience of the diagnosis seems to have been lived as a traumatic break that has created a dichotomy, like an ambivalence in the ways in which CML patients perceived and experienced the whole disease journey, with contradictory feelings of both positive and negative emotions (e.g., a diagnosis of cancer, that is something distressing and of being afraid of, but also with a treatment and a life expectancies of which being grateful). This ambivalence of feelings was found to give meaning to the way in which patients cognitively and emotionally experienced the different steps of their disease history. Thus, four main issues, corresponding to different steps of the patients' journey, were identified: (1) the moment of the diagnosis, (2) the experience of the illness journey: disease and treatment, (3) the moment of "TFR failure," and (4) the impact of disease, treatment and relapse on the patient's life. Conclusion: This qualitative analysis helps in understanding patients' perspective, both in terms of getting access to the inner subjective experience of having CML and its strict relationship with the involvement in a trial or its cessation. Clinicians should consider that the way in which CML patients feel engaged in a clinical trial, create expectancies about TFR or experience the TFR failure is linked to the process of coping with the diagnosis, which is characterized by ambivalence

    A proteomics analysis of 5xFAD mouse brain regions reveals the lysosome-associated protein Arl8b as a candidate biomarker for Alzheimer’s disease

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    BACKGROUND: Alzheimer's disease (AD) is characterized by the intra- and extracellular accumulation of amyloid-ß (Aß) peptides. How Aß aggregates perturb the proteome in brains of patients and AD transgenic mouse models, remains largely unclear. State-of-the-art mass spectrometry (MS) methods can comprehensively detect proteomic alterations, providing relevant insights unobtainable with transcriptomics investigations. Analyses of the relationship between progressive Aß aggregation and protein abundance changes in brains of 5xFAD transgenic mice have not been reported previously. METHODS: We quantified progressive Aß aggregation in hippocampus and cortex of 5xFAD mice and controls with immunohistochemistry and membrane filter assays. Protein changes in different mouse tissues were analyzed by MS-based proteomics using label-free quantification; resulting MS data were processed using an established pipeline. Results were contrasted with existing proteomic data sets from postmortem AD patient brains. Finally, abundance changes in the candidate marker Arl8b were validated in cerebrospinal fluid (CSF) from AD patients and controls using ELISAs. RESULTS: Experiments revealed faster accumulation of Aß42 peptides in hippocampus than in cortex of 5xFAD mice, with more protein abundance changes in hippocampus, indicating that Aß42 aggregate deposition is associated with brain region-specific proteome perturbations. Generating time-resolved data sets, we defined Aß aggregate-correlated and anticorrelated proteome changes, a fraction of which was conserved in postmortem AD patient brain tissue, suggesting that proteome changes in 5xFAD mice mimic disease-relevant changes in human AD. We detected a positive correlation between Aß42 aggregate deposition in the hippocampus of 5xFAD mice and the abundance of the lysosome-associated small GTPase Arl8b, which accumulated together with axonal lysosomal membranes in close proximity of extracellular Aß plaques in 5xFAD brains. Abnormal aggregation of Arl8b was observed in human AD brain tissue. Arl8b protein levels were significantly increased in CSF of AD patients. CONCLUSIONS: We report a comprehensive biochemical and proteomic investigation of hippocampal and cortical brain tissue derived from 5xFAD transgenic mice, providing a valuable resource to the neuroscientific community. We identified Arl8b, with significant abundance changes in 5xFAD and AD patient brains. Arl8b might enable the measurement of progressive lysosome accumulation in AD patients and have clinical utility as a candidate biomarker

    Interactome mapping provides a network of neurodegenerative disease proteins and uncovers widespread protein aggregation in affected brains

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    Interactome maps are valuable resources to elucidate protein function and disease mechanisms. Here, we report on an interactome map that focuses on neurodegenerative disease (ND), connects ∼5,000 human proteins via ∼30,000 candidate interactions and is generated by systematic yeast two-hybrid interaction screening of ∼500 ND-related proteins and integration of literature interactions. This network reveals interconnectivity across diseases and links many known ND-causing proteins, such as α-synuclein, TDP-43, and ATXN1, to a host of proteins previously unrelated to NDs. It facilitates the identification of interacting proteins that significantly influence mutant TDP-43 and HTT toxicity in transgenic flies, as well as of ARF-GEP(100) that controls misfolding and aggregation of multiple ND-causing proteins in experimental model systems. Furthermore, it enables the prediction of ND-specific subnetworks and the identification of proteins, such as ATXN1 and MKL1, that are abnormally aggregated in postmortem brains of Alzheimer's disease patients, suggesting widespread protein aggregation in NDs

    Cloning and expression analysis of the chick ortholog of TBX22, the gene mutated in X-linked cleft palate and ankyloglossia

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    T-box genes constitute a conserved gene family with important roles in many developmental processes. Several family members have been implicated in human congenital diseases. Recently, mutations in TBX22 were found to cause X-linked cleft palate (CPX and ankyloglossia), a semidominant X-linked disorder affecting formation of the secondary palate. Here, we have cloned the chick ortholog of human TBX22 and have analyzed its expression during embryogenesis. Expression is very prominent in the somites and ill the myotome, and in the mandible and maxilla of the developing jaw. Other sites of expression include the limbs, the cranial mesenchyme and the eye. Hence, Tbx22 expression domains encompass the regions important for the development of the disease phenotype. (C) 2002 Elsevier Science Ireland Ltd. All rights reserved

    Method for the identification of protein-protein interactions in disease related protein networks [Verfahren zur Identifizierung von Protein-Protein-Wechselwirkungen in krankheitsbezogenen Proteinnetzwerken]

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    The present invention relates to a method for identification of a protein-protein interaction of protein interaction partners in a disease-related network of proteins comprising the steps of (a) identifying nucleic acid molecules by at least partial 5'sequencing and, optionally, additionally adding recombinantly cloned and sequenced nucleic acid molecules, wherein said nucleic acid molecules encode a selection of proteins suspected to contain one or several of said interaction partners and wherein said nucleic acid molecules are annotated with a positional information; (b) in frame cloning of the nucleic acid molecules of step (a) into prey and bait vectors, wherein one copy of each nucleic acid molecule is cloned into said prey vector and a second copy of each nucleic acid molecule is cloned into said bait vector; (c) transforming a first suitable host cell with the prey vector obtained in step (b) and a second suitable host cell with the bait vector obtained in step (b), wherein said first and said second host cell have a different genetic constitution and can be mated; (d) mating the first suitable host cell of step (c) with the second suitable host cell of step (c), and expressing the proteins encoded by the nucleic acid molecules obtained in step (b); (e) selecting the mated host cell obtained in step (d) on the basis of a selection advantage which is caused by the protein-protein interaction between the protein interaction partner encoded by the nucleic acid molecule of the prey vector contained in said cell and the protein interaction partner encoded by the nucleic acid molecule of the bait vector contained in said cell; and (f) identifying with the positional information obtained in step (a) the protein interaction partners of step (e) and thereby identifying the protein-protein interaction
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