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1.
Nucleic Acids Res ; 2024 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-38801081

RESUMEN

Dealing with sequence coordinates in different formats and reference genomes is challenging in genetic research. This complexity arises from the need to convert and harmonize datasets of different sources using alternating nomenclatures. Since manual processing is time-consuming and requires specialized knowledge, the Sequence Conversion and Analysis Toolbox (SeqCAT) was developed for daily work with genetic datasets. Our tool provides a range of functions designed to standardize and convert gene variant coordinates based on various sequence types. Its user-friendly web interface provides easy access to all functionalities, while the Application Programming Interface (API) enables automation within pipelines. SeqCAT provides access to human genomic, protein and transcript data, utilizing various data resources and packages and extending them with its own unique features. The platform covers a wide range of genetic research needs with its 14 different applications and 3 info points, including search for transcript and gene information, transition between reference genomes, variant mapping, and genetic event review. Notable examples are 'Convert Protein to DNA Position' for translation of amino acid changes into genomic single nucleotide variants, or 'Fusion Check' for frameshift determination in gene fusions. SeqCAT is an excellent resource for converting sequence coordinate data into the required formats and is available at: https://mtb.bioinf.med.uni-goettingen.de/SeqCAT/.

2.
Bioinformatics ; 40(Supplement_1): i91-i99, 2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-38940173

RESUMEN

MOTIVATION: High-throughput screens (HTS) provide a powerful tool to decipher the causal effects of chemical and genetic perturbations on cancer cell lines. Their ability to evaluate a wide spectrum of interventions, from single drugs to intricate drug combinations and CRISPR-interference, has established them as an invaluable resource for the development of novel therapeutic approaches. Nevertheless, the combinatorial complexity of potential interventions makes a comprehensive exploration intractable. Hence, prioritizing interventions for further experimental investigation becomes of utmost importance. RESULTS: We propose CODEX (COunterfactual Deep learning for the in silico EXploration of cancer cell line perturbations) as a general framework for the causal modeling of HTS data, linking perturbations to their downstream consequences. CODEX relies on a stringent causal modeling strategy based on counterfactual reasoning. As such, CODEX predicts drug-specific cellular responses, comprising cell survival and molecular alterations, and facilitates the in silico exploration of drug combinations. This is achieved for both bulk and single-cell HTS. We further show that CODEX provides a rationale to explore complex genetic modifications from CRISPR-interference in silico in single cells. AVAILABILITY AND IMPLEMENTATION: Our implementation of CODEX is publicly available at https://github.com/sschrod/CODEX. All data used in this article are publicly available.


Asunto(s)
Simulación por Computador , Aprendizaje Profundo , Humanos , Línea Celular Tumoral , Ensayos Analíticos de Alto Rendimiento/métodos , Neoplasias/metabolismo , Biología Computacional/métodos , Programas Informáticos , Antineoplásicos/farmacología
3.
Bioinformatics ; 40(Supplement_1): i100-i109, 2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-38940181

RESUMEN

MOTIVATION: The inference of cellular compositions from bulk and spatial transcriptomics data increasingly complements data analyses. Multiple computational approaches were suggested and recently, machine learning techniques were developed to systematically improve estimates. Such approaches allow to infer additional, less abundant cell types. However, they rely on training data which do not capture the full biological diversity encountered in transcriptomics analyses; data can contain cellular contributions not seen in the training data and as such, analyses can be biased or blurred. Thus, computational approaches have to deal with unknown, hidden contributions. Moreover, most methods are based on cellular archetypes which serve as a reference; e.g. a generic T-cell profile is used to infer the proportion of T-cells. It is well known that cells adapt their molecular phenotype to the environment and that pre-specified cell archetypes can distort the inference of cellular compositions. RESULTS: We propose Adaptive Digital Tissue Deconvolution (ADTD) to estimate cellular proportions of pre-selected cell types together with possibly unknown and hidden background contributions. Moreover, ADTD adapts prototypic reference profiles to the molecular environment of the cells, which further resolves cell-type specific gene regulation from bulk transcriptomics data. We verify this in simulation studies and demonstrate that ADTD improves existing approaches in estimating cellular compositions. In an application to bulk transcriptomics data from breast cancer patients, we demonstrate that ADTD provides insights into cell-type specific molecular differences between breast cancer subtypes. AVAILABILITY AND IMPLEMENTATION: A python implementation of ADTD and a tutorial are available at Gitlab and zenodo (doi:10.5281/zenodo.7548362).


Asunto(s)
Aprendizaje Automático , Humanos , Perfilación de la Expresión Génica/métodos , Neoplasias de la Mama/genética , Neoplasias de la Mama/metabolismo , Transcriptoma , Algoritmos , Biología Computacional/métodos , Femenino
4.
Biol Proced Online ; 26(1): 7, 2024 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-38504200

RESUMEN

BACKGROUND: Osteoclasts are the tissue-specific macrophage population of the bone and unique in their bone-resorbing activity. Hence, they are fundamental for bone physiology in health and disease. However, efficient protocols for the isolation and study of primary human osteoclasts are scarce. In this study, we aimed to establish a protocol, which enables the efficient differentiation of functional human osteoclasts from monocytes. RESULTS: Human monocytes were isolated through a double-density gradient from donor blood. Compared to standard differentiation schemes in polystyrene cell culture dishes, the yield of multinuclear osteoclasts was significantly increased upon initial differentiation of monocytes to macrophages in fluorinated ethylene propylene (FEP) Teflon bags. This initial differentiation phase was then followed by the development of terminal osteoclasts by addition of Receptor Activator of NF-κB Ligand (RANKL). High concentrations of RANKL and Macrophage colony-stimulating factor (M-CSF) as well as an intermediate cell density further supported efficient cell differentiation. The generated cells were highly positive for CD45, CD14 as well as the osteoclast markers CD51/ITGAV and Cathepsin K/CTSK, thus identifying them as osteoclasts. The bone resorption of the osteoclasts was significantly increased when the cells were differentiated from macrophages derived from Teflon bags compared to macrophages derived from conventional cell culture plates. CONCLUSION: Our study has established a novel protocol for the isolation of primary human osteoclasts that improves osteoclastogenesis in comparison to the conventionally used cultivation approach.

5.
Bioinformatics ; 39(11)2023 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-37988152

RESUMEN

SUMMARY: Federated learning enables collaboration in medicine, where data is scattered across multiple centers without the need to aggregate the data in a central cloud. While, in general, machine learning models can be applied to a wide range of data types, graph neural networks (GNNs) are particularly developed for graphs, which are very common in the biomedical domain. For instance, a patient can be represented by a protein-protein interaction (PPI) network where the nodes contain the patient-specific omics features. Here, we present our Ensemble-GNN software package, which can be used to deploy federated, ensemble-based GNNs in Python. Ensemble-GNN allows to quickly build predictive models utilizing PPI networks consisting of various node features such as gene expression and/or DNA methylation. We exemplary show the results from a public dataset of 981 patients and 8469 genes from the Cancer Genome Atlas (TCGA). AVAILABILITY AND IMPLEMENTATION: The source code is available at https://github.com/pievos101/Ensemble-GNN, and the data at Zenodo (DOI: 10.5281/zenodo.8305122).


Asunto(s)
Metilación de ADN , Aprendizaje Automático , Humanos , Redes Neurales de la Computación , Mapas de Interacción de Proteínas , Programas Informáticos
6.
Mol Cancer ; 22(1): 17, 2023 01 24.
Artículo en Inglés | MEDLINE | ID: mdl-36691028

RESUMEN

BACKGROUND: Colorectal cancer liver metastases (CRCLM) are associated with a poor prognosis, reflected by a five-year survival rate of 14%. Anti-angiogenic therapy through anti-VEGF antibody administration is one of the limited therapies available. However, only a subgroup of metastases uses sprouting angiogenesis to secure their nutrients and oxygen supply, while others rely on vessel co-option (VCO). The distinct mode of vascularization is reflected by specific histopathological growth patterns (HGPs), which have proven prognostic and predictive significance. Nevertheless, their molecular mechanisms are poorly understood. METHODS: We evaluated CRCLM from 225 patients regarding their HGP and clinical data. Moreover, we performed spatial (21,804 spots) and single-cell (22,419 cells) RNA sequencing analyses to explore molecular differences in detail, further validated in vitro through immunohistochemical analysis and patient-derived organoid cultures. RESULTS: We detected specific metabolic alterations and a signature of WNT signalling activation in metastatic cancer cells related to the VCO phenotype. Importantly, in the corresponding healthy liver of CRCLM displaying sprouting angiogenesis, we identified a predominantly expressed capillary subtype of endothelial cells, which could be further explored as a possible predictor for HGP relying on sprouting angiogenesis. CONCLUSION: These findings may prove to be novel therapeutic targets to the treatment of CRCLM, in special the ones relying on VCO.


Asunto(s)
Neoplasias Colorrectales , Neoplasias Hepáticas , Humanos , Células Endoteliales/patología , Neoplasias Hepáticas/genética , Neovascularización Patológica/patología , Neoplasias Colorrectales/patología
7.
Mol Cell ; 59(2): 243-57, 2015 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-26145175

RESUMEN

Proteasome inhibition represents a promising strategy of cancer pharmacotherapy, but resistant tumor cells often emerge. Here we show that the microRNA-101 (miR-101) targets the proteasome maturation protein POMP, leading to impaired proteasome assembly and activity, and resulting in accumulation of p53 and cyclin-dependent kinase inhibitors, cell cycle arrest, and apoptosis. miR-101-resistant POMP restores proper turnover of proteasome substrates and re-enables tumor cell growth. In ERα-positive breast cancers, miR-101 and POMP levels are inversely correlated, and high miR-101 expression or low POMP expression associates with prolonged survival. Mechanistically, miR-101 expression or POMP knockdown attenuated estrogen-driven transcription. Finally, suppressing POMP is sufficient to overcome tumor cell resistance to the proteasome inhibitor bortezomib. Taken together, proteasome activity can not only be manipulated through drugs, but is also subject to endogenous regulation through miR-101, which targets proteasome biogenesis to control overall protein turnover and tumor cell proliferation.


Asunto(s)
MicroARNs/genética , MicroARNs/metabolismo , Chaperonas Moleculares/genética , Chaperonas Moleculares/metabolismo , Inhibidores de Proteasoma/metabolismo , Regiones no Traducidas 3' , Animales , Apoptosis , Ácidos Borónicos/farmacología , Bortezomib , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/genética , Neoplasias de la Mama/metabolismo , Puntos de Control del Ciclo Celular , Línea Celular Tumoral , Proliferación Celular , Proteínas Inhibidoras de las Quinasas Dependientes de la Ciclina/metabolismo , Resistencia a Antineoplásicos/genética , Receptor alfa de Estrógeno/metabolismo , Femenino , Técnicas de Silenciamiento del Gen , Células HCT116 , Células Hep G2 , Humanos , Células MCF-7 , Ratones , Chaperonas Moleculares/antagonistas & inhibidores , Complejo de la Endopetidasa Proteasomal/metabolismo , Inhibidores de Proteasoma/farmacología , Pirazinas/farmacología , ARN Interferente Pequeño/genética , Proteína p53 Supresora de Tumor/metabolismo
8.
Br J Cancer ; 127(4): 766-775, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35597871

RESUMEN

PURPOSE: Preoperative (neoadjuvant) chemoradiotherapy (CRT) and total mesorectal excision is the standard treatment for rectal cancer patients (UICC stage II/III). Up to one-third of patients treated with CRT achieve a pathological complete response (pCR). These patients could be spared from surgery and its associated morbidity and mortality, and assigned to a "watch and wait" strategy. However, reliably identifying pCR based on clinical or imaging parameters remains challenging. EXPERIMENTAL DESIGN: We generated gene-expression profiles of 175 patients with locally advanced rectal cancer enrolled in the CAO/ARO/AIO-94 and -04 trials. One hundred and sixty-one samples were used for building, training and validating a predictor of pCR using a machine learning algorithm. The performance of the classifier was validated in three independent cohorts, comprising 76 patients from (i) the CAO/ARO/AIO-94 and -04 trials (n = 14), (ii) a publicly available dataset (n = 38) and (iii) in 24 prospectively collected samples from the TransValid A trial. RESULTS: A 21-transcript signature yielded the best classification of pCR in 161 patients (Sensitivity: 0.31; AUC: 0.81), when not allowing misclassification of non-complete-responders (False-positive rate = 0). The classifier remained robust when applied to three independent datasets (n = 76). CONCLUSION: The classifier can identify >1/3 of rectal cancer patients with a pCR while never classifying patients with an incomplete response as having pCR. Importantly, we could validate this finding in three independent datasets, including a prospectively collected cohort. Therefore, this classifier could help select rectal cancer patients for a "watch and wait" strategy. TRANSLATIONAL RELEVANCE: Forgoing surgery with its associated side effects could be an option for rectal cancer patients if the prediction of a pathological complete response (pCR) after preoperative chemoradiotherapy would be possible. Based on gene-expression profiles of 161 patients a classifier was developed and validated in three independent datasets (n = 76), identifying over 1/3 of patients with pCR, while never misclassifying a non-complete-responder. Therefore, the classifier can identify patients suited for "watch and wait".


Asunto(s)
Quimioradioterapia , Neoplasias del Recto , Biopsia , Ensayos Clínicos como Asunto , Humanos , Terapia Neoadyuvante , Neoplasias del Recto/genética , Neoplasias del Recto/patología , Neoplasias del Recto/terapia , Resultado del Tratamiento
9.
BMC Cancer ; 21(1): 1296, 2021 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-34863149

RESUMEN

BACKGROUND: Triple negative breast cancer (TNBC) is the most aggressive subtype of breast cancer (BC). Treatment options for TNBC patients are limited and further insights into disease aetiology are needed to develop better therapeutic approaches. microRNAs' ability to regulate multiple targets could hold a promising discovery approach to pathways relevant for TNBC aggressiveness. Thus, we address the role of miRNAs in controlling three signalling pathways relevant to the biology of TNBC, and their downstream phenotypes. METHODS: To identify miRNAs regulating WNT/ß-catenin, c-Met, and integrin signalling pathways, we performed a high-throughput targeted proteomic approach, investigating the effect of 800 miRNAs on the expression of 62 proteins in the MDA-MB-231 TNBC cell line. We then developed a novel network analysis, Pathway Coregulatory (PC) score, to detect miRNAs regulating these three pathways. Using in vitro assays for cell growth, migration, apoptosis, and stem-cell content, we validated the function of candidate miRNAs. Bioinformatic analyses using BC patients' datasets were employed to assess expression of miRNAs as well as their pathological relevance in TNBC patients. RESULTS: We identified six candidate miRNAs coordinately regulating the three signalling pathways. Quantifying cell growth of three TNBC cell lines upon miRNA gain-of-function experiments, we characterised miR-193b as a strong and consistent repressor of proliferation. Importantly, the effects of miR-193b were stronger than chemical inhibition of the individual pathways. We further demonstrated that miR-193b induced apoptosis, repressed migration, and regulated stem-cell markers in MDA-MB-231 cells. Furthermore, miR-193b expression was the lowest in patients classified as TNBC or Basal compared to other subtypes. Gene Set Enrichment Analysis showed that miR-193b expression was significantly associated with reduced activity of WNT/ß-catenin and c-Met signalling pathways in TNBC patients. CONCLUSIONS: Integrating miRNA-mediated effects and protein functions on networks, we show that miRNAs predominantly act in a coordinated fashion to activate or repress connected signalling pathways responsible for metastatic traits in TNBC. We further demonstrate that our top candidate, miR-193b, regulates these phenotypes to an extent stronger than individual pathway inhibition, thus emphasizing that its effect on TNBC aggressiveness is mediated by the coordinated repression of these functionally interconnected pathways.


Asunto(s)
MicroARNs/metabolismo , Proteínas Proto-Oncogénicas c-met/metabolismo , Neoplasias de la Mama Triple Negativas/genética , Vía de Señalización Wnt/genética , beta Catenina/metabolismo , Línea Celular Tumoral , Proliferación Celular , Humanos , Metástasis de la Neoplasia , Transfección
10.
BMC Cancer ; 21(1): 219, 2021 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-33663399

RESUMEN

BACKGROUND: The question whether lymphocyte radiosensitivity is representative of patients' response to radiotherapy (RT) remains unsolved. We analyzed lymphocyte cytogenetic damage in patients who were homogeneously treated with preoperative radiochemotherapy (RCT) for rectal cancer within clinical trials. We tested for interindividual variation and consistent radiosensitivity after in-vivo and in-vitro irradiation, analyzed the effect of patients' and RCT characteristics on cytogenetic damage, and tested for correlations with patients' outcome in terms of tumor response, survival and treatment-related toxicity. METHODS: The cytokinesis-block micronucleus cytome (CBMNcyt) assay was performed on the peripheral blood lymphocytes (PBLCs) of 134 patients obtained before, during, at the end of RCT, and during the 2-year follow-up. A subset of PBLCs obtained before RCT was irradiated in-vitro with 3 Gy. RCT included 50.4 Gy of pelvic RT with 5-fluorouracil (5-FU) alone (n = 78) or 5-FU plus oxaliplatin (n = 56). The analyzed variables included patients' age, gender, RT characteristics (planning target volume size [PTV size], RT technique), and chemotherapy characteristics (5-FU plasma levels, addition of oxaliplatin). Outcome was analyzed as tumor regression, patient survival, and acute and late toxicity. RESULTS: Cytogenetic damage increased significantly with the radiation dose and varied substantially between individuals. Women were more sensitive than men; no significant age-dependent differences were observed. There was a significant correlation between the cytogenetic damage after in-vitro irradiation and in-vivo RCT. We found a significant effect of the PTV size on the yields of cytogenetic damage after RCT, while the RT technique had no effect. Neither the addition of oxaliplatin nor the 5-FU levels influenced cytogenetic damage. We found no correlation between patient outcome and the cytogenetic damage. CONCLUSIONS: We found consistent cytogenetic damage in lymphocytes after in-vivo RCT and in-vitro irradiation. Gender was confirmed as a well-known, and the PTV size was identified as a less well-known influencing variable on lymphocyte cytogenetic damage after partial-body irradiation. A consistent level of cytogenetic damage after in-vivo and in-vitro irradiation may indicate the importance of genetic factors for individual radiosensitivity. However, we found no evidence that in-vivo or in-vitro irradiation-induced cytogenetic damage is an adequate biomarker for the response to RCT in rectal cancer patients.


Asunto(s)
Quimioradioterapia/métodos , Micronúcleos con Defecto Cromosómico , Neoplasias del Recto/terapia , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Pruebas de Micronúcleos , Persona de Mediana Edad , Terapia Neoadyuvante , Pronóstico , Neoplasias del Recto/genética , Neoplasias del Recto/mortalidad
11.
Digestion ; 102(2): 265-273, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-31962319

RESUMEN

INTRODUCTION: Local recurrence remains a major problem after pancreatic head resection. Intensified histopathological work-up of surgical specimens after pancreatic head resection has revealed an increased number of incomplete resections (R1) depending on tumor infiltration front at the resection margins (RMs). It remains unclear to which extent the increased R1 resection rate has a clinical relevance for the patients' prognosis. MATERIALS AND METHODS: Pancreatic head resections between 2006 and 2012 were histologically intensively worked-up by a previously described protocol. The distance between the tumor infiltration front and the resection planes or organ surfaces was documented. The impact of the size of the tumor and an additional portal vein resection was analyzed. The effect of a R1 resection status on development and type of recurrence was evaluated. RESULTS: A total of 203 pancreatic head resections were evaluated. Different definitions of R1 resection were applied. These led to significantly different prognosis for patients. A greater distance between the tumor infiltration front and the resection plane or organ surface was associated with a better outcome for the patients. For the ventral surface, the mesopancreas and the pancreatic body these differences were statistically significant comparing the different R1 definitions. For the dorsal surface, a significant difference in prognosis was found if the tumor was >2 mm away from the resection surface. A tumor size of 3 cm was identified to play a relevant role for the prognosis. Patients who had a portal vein resection without a histologically proven infiltration showed a statistically significant higher overall survival. Patients with R1 resection were at highest risk for developing local recurrence as well as distant metastasis. CONCLUSION: Intensified histopathological work-up with an increased number of R1 resections has a clinical relevance for patients' prognosis. Tumors with a smaller size or with a greater distance to the organ surface or RM have a better outcome.


Asunto(s)
Neoplasias Pancreáticas , Humanos , Recurrencia Local de Neoplasia , Páncreas/diagnóstico por imagen , Páncreas/cirugía , Pancreatectomía , Neoplasias Pancreáticas/cirugía , Pancreaticoduodenectomía , Pronóstico , Estudios Retrospectivos , Tasa de Supervivencia
12.
Med Teach ; 43(5): 524-530, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33502287

RESUMEN

BACKGROUND: Low response rates threaten the reliability and validity of student evaluations of teaching. Previous research has shown that asking students to predict how satisfied their fellow students were with a course produces reliable results at lower response rates. The aim of this study was to investigate whether this prediction-based method can also be used to evaluate student learning outcome. METHODS: Before and after a cardiorespiratory module, 128 fourth-year medical students provided self-assessments and predictions of performance on 27 specific learning objectives and took formative tests on the respective contents. Pre-post performance gain was compared across all three modalities. RESULTS: Formative exam results indicated a performance gain of 63.0%. Self-assessed and prediction-based performance gains were identical (67.8%) but both slightly overestimated actual performance gain. Irrespective of the method used, a response rate of 20% was sufficient to produce reliable results. Compared to male students, females greatly overestimated their peers' performance which led to inflated performance gain values. CONCLUSIONS: Student self-assessments and predictions are equally valid sources of learning outcome measures, and low response rates are sufficient to produce stable results. When using a prediction-based approach, a tendency to overestimate learning outcome in female students needs to be taken into account.


Asunto(s)
Educación de Pregrado en Medicina , Estudiantes de Medicina , Curriculum , Evaluación Educacional , Femenino , Humanos , Masculino , Reproducibilidad de los Resultados , Autoevaluación (Psicología) , Factores Sexuales
13.
Acta Neuropathol ; 139(3): 547-564, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31950335

RESUMEN

Early active multiple sclerosis (MS) lesions can be classified histologically into three main immunopathological patterns of demyelination (patterns I-III), which suggest pathogenic heterogeneity and may predict therapy response. Patterns I and II show signs of immune-mediated demyelination, but only pattern II is associated with antibody/complement deposition. In pattern III lesions, which include Baló's concentric sclerosis, primary oligodendrocyte damage was proposed. Serum antibody reactivities could reflect disease pathogenesis and thus distinguish histopathologically defined MS patterns. We established a customized microarray with more than 700 peptides that represent human and viral antigens potentially relevant for inflammatory demyelinating CNS diseases, and tested sera from 66 patients (pattern I n = 12; II n = 29; III n = 25, including 8 with Baló's), healthy controls, patients with Sjögren's syndrome and stroke patients. Cell-based assays were performed for aquaporin 1 (AQP1) and AQP4 antibody detection. No single peptide showed differential binding among study cohorts. Because antibodies can react with different peptides from one protein, we also analyzed groups of peptides. Patients with pattern II showed significantly higher reactivities to Nogo-A peptides as compared to patterns I (p = 0.02) and III (p = 0.02). Pattern III patients showed higher reactivities to AQP1 (compared to pattern I p = 0.002, pattern II p = 0.001) and varicella zoster virus (VZV, compared to pattern II p = 0.05). In patients with Baló's, AQP1 reactivity was also significantly higher compared to patients without Baló's (p = 0.04), and the former revealed distinct antibody signatures. Histologically, Baló's patients showed loss of AQP1 and AQP4 in demyelinating lesions, but no antibodies binding conformational AQP1 or AQP4 were detected. In summary, higher reactivities to Nogo-A peptides in pattern II patients could be relevant for enhanced axonal repair and remyelination. Higher reactivities to AQP1 peptides in pattern III patients and its subgroup of Baló's patients possibly reflect astrocytic damage. Finally, latent VZV infection may cause peripheral immune activation.


Asunto(s)
Autoanticuerpos/inmunología , Esclerosis Múltiple/clasificación , Esclerosis Múltiple/inmunología , Esclerosis Múltiple/patología , Adulto , Acuaporina 1/inmunología , Acuaporina 4/inmunología , Autoantígenos/inmunología , Esclerosis Cerebral Difusa de Schilder/clasificación , Esclerosis Cerebral Difusa de Schilder/inmunología , Esclerosis Cerebral Difusa de Schilder/patología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neuromielitis Óptica/clasificación , Neuromielitis Óptica/inmunología , Neuromielitis Óptica/patología
14.
BMC Cancer ; 20(1): 973, 2020 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-33032552

RESUMEN

BACKGROUND: Brain metastasis represents a major complication with a significantly shorter overall survival of many oncological diseases, in particular of lung cancer, breast cancer and malignant melanoma patients. However, despite the poor prognosis, sometimes clinical decision-making, between on the one hand not to harm the patient and on the other hand not withholding a potential therapeutic option, is very challenging. Thus the aim of this retrospective study was to compare various scores, including scores for activities of daily living (ADL) before resection of brain metastases and to analyse their impact on survival. METHODS: Our single institution retrospective patient cohort (N = 100) with a median age of 63.6 years, which had all undergone resection of one or more brain metastases, was categorized using the original patient files. The cohort includes 52 patients with lung cancer, 27 patients with breast cancer, 8 patients with colorectal carcinoma and 13 patients with kidney cancer. To categorize, we used different score systems which were capable to evaluate the patient in relation to self-sufficiency, activity and self-determination as part of ADL. The retrospective analysis includes the ECOG-Status, Karnofsky-Index, Barthel-Index, ASA-Classification and Katz-Index. Pre-processing and the analysis of the data was implemented using KNIME, where we used the R-plugin nodes to perform the final statistical tests with R. RESULTS: Our analysis reveals that most of the ADL scores we tested are able to give a reliable prediction on overall survival after brain metastasis surgery. The survival rates decrease significantly with a lower score in all tested score systems, with the exception of the ASA-Risk score. In particular, the Katz Index < 6 was identified to have a significant correlation with a lower cancer specific survival (CSS) (HR 3.33, 95%-CI [2.17-5.00]; p-Value = 9.6*10- 9), which is easy to use and has reproducible measurements. CONCLUSIONS: Pre-operative independence assessment by indices of ADL represents a predictor for overall survival after resection of brain metastases. Especially the easily, objectively and rapidly applicable Katz-Score is a very helpful tool to assess the pre-operative status, which could be additionally included in clinical decision making in daily practice.


Asunto(s)
Neoplasias Encefálicas/mortalidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Periodo Preoperatorio , Pronóstico , Tasa de Supervivencia
15.
Mol Cell ; 46(5): 705-13, 2012 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-22681891

RESUMEN

Extensive changes in posttranslational histone modifications accompany the rewiring of the transcriptional program during stem cell differentiation. However, the mechanisms controlling the changes in specific chromatin modifications and their function during differentiation remain only poorly understood. We show that histone H2B monoubiquitination (H2Bub1) significantly increases during differentiation of human mesenchymal stem cells (hMSCs) and various lineage-committed precursor cells and in diverse organisms. Furthermore, the H2B ubiquitin ligase RNF40 is required for the induction of differentiation markers and transcriptional reprogramming of hMSCs. This function is dependent upon CDK9 and the WAC adaptor protein, which are required for H2B monoubiquitination. Finally, we show that RNF40 is required for the resolution of the H3K4me3/H3K27me3 bivalent poised state on lineage-specific genes during the transition from an inactive to an active chromatin conformation. Thus, these data indicate that H2Bub1 is required for maintaining multipotency of hMSCs and plays a central role in controlling stem cell differentiation.


Asunto(s)
Diferenciación Celular/genética , Histonas/metabolismo , Células Madre Mesenquimatosas/citología , Células Madre Multipotentes/citología , Proteínas Adaptadoras Transductoras de Señales/genética , Proteínas Adaptadoras Transductoras de Señales/fisiología , Línea Celular , Ensamble y Desensamble de Cromatina , Quinasa 9 Dependiente de la Ciclina/genética , Quinasa 9 Dependiente de la Ciclina/fisiología , Humanos , Células Madre Mesenquimatosas/metabolismo , Células Madre Multipotentes/metabolismo , Procesamiento Proteico-Postraduccional , Ubiquitina-Proteína Ligasas/genética , Ubiquitina-Proteína Ligasas/metabolismo , Ubiquitina-Proteína Ligasas/fisiología , Ubiquitinación
16.
Int J Mol Sci ; 21(21)2020 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-33171904

RESUMEN

Background: Previous studies have reported the fundamental role of immunoregulatory proteins in the clinical phenotype and outcome of sepsis. This study investigated two functional single nucleotide polymorphisms (SNPs) of T cell immunoglobulin and mucin domain-containing protein 3 (TIM-3), which has a negative stimulatory function in the T cell immune response. Methods: Patients with sepsis (n = 712) were prospectively enrolled from three intensive care units (ICUs) at the University Medical Center Goettingen since 2012. All patients were genotyped for the TIM-3 SNPs rs1036199 and rs10515746. The primary outcome was 28-day mortality. Disease severity and microbiological findings were secondary endpoints. Results: Kaplan-Meier survival analysis demonstrated a significantly lower 28-day mortality for TIM-3 rs1036199 AA homozygous patients compared to C-allele carriers (18% vs. 27%, p = 0.0099) and TIM-3 rs10515746 CC homozygous patients compared to A-allele carriers (18% vs. 26%, p = 0.0202). The TIM-3 rs1036199 AA genotype and rs10515746 CC genotype remained significant predictors for 28-day mortality in the multivariate Cox regression analysis after adjustment for relevant confounders (adjusted hazard ratios: 0.67 and 0.70). Additionally, patients carrying the rs1036199 AA genotype presented more Gram-positive and Staphylococcus epidermidis infections, and rs10515746 CC homozygotes presented more Staphylococcus epidermidis infections. Conclusion: The studied TIM-3 genetic variants are associated with altered 28-day mortality and susceptibility to Gram-positive infections in sepsis.


Asunto(s)
Receptor 2 Celular del Virus de la Hepatitis A/genética , Sepsis/genética , Sepsis/mortalidad , Adulto , Anciano , Alelos , Estudios de Casos y Controles , Femenino , Frecuencia de los Genes/genética , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad/genética , Genotipo , Receptor 2 Celular del Virus de la Hepatitis A/metabolismo , Heterocigoto , Homocigoto , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple/genética , Índice de Severidad de la Enfermedad
17.
Int J Cancer ; 145(8): 2282-2291, 2019 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-30868576

RESUMEN

Peripheral blood leukocytosis and neutrophilia reflect cancer inflammation and have been proposed as prognostic immunological biomarkers in various malignancies. However, previous studies were limited by their retrospective nature and small patient numbers. Baseline peripheral blood leukocytes, neutrophils, hemoglobin, platelets, lactate dehydrogenase and carcinoembryonic antigen (CEA) were correlated with clinicopathologic characteristics, and clinical outcome in 1236 patients with rectal cancer treated with 5-FU-based preoperative chemoradiotherapy (CRT) alone or with oxaliplatin followed by surgery and adjuvant chemotherapy within the CAO/ARO/AIO-04 randomized phase 3 trial. Multivariable analyses were performed using Cox regression models. After a median follow-up of 50 months, baseline leukocytosis remained an independent adverse prognostic factor for disease-free survival (DFS; HR 1.457; 95% CI 1.163-1.825; p = 0.001), distant metastasis (HR 1.696; 95% CI 1.266-2.273; p < 0.001) and overall survival (OS; HR 1.716; 95% CI 1.264-2.329; p = 0.001) in multivariable analysis. Similar significant findings were observed for neutrophilia and high CEA levels. Conversely, treatment-induced leukopenia correlated with favorable DFS (p = 0.037), distant metastasis (p = 0.028) and OS (p = 0.012). Intriguingly, addition of oxaliplatin to 5-FU CRT resulted in a significant DFS improvement only in patients with neutrophilia and leukocytosis (p = 0.028 and p = 0.002). Our findings have important clinical implications and provide high-level evidence on the adverse prognostic role of leukocytes and neutrophils, and the impact of chemotherapy in the context of these biomarkers. These data could help guide patient stratification and should be further validated within prospective studies.


Asunto(s)
Biomarcadores de Tumor/sangre , Fluorouracilo/uso terapéutico , Leucocitosis/sangre , Neutrófilos , Oxaliplatino/uso terapéutico , Neoplasias del Recto/terapia , Anciano , Antineoplásicos/uso terapéutico , Quimioradioterapia Adyuvante/métodos , Quimioterapia Adyuvante/métodos , Supervivencia sin Enfermedad , Femenino , Humanos , Recuento de Leucocitos , Masculino , Persona de Mediana Edad , Evaluación de Resultado en la Atención de Salud/métodos , Evaluación de Resultado en la Atención de Salud/estadística & datos numéricos , Pronóstico , Modelos de Riesgos Proporcionales , Neoplasias del Recto/sangre , Neoplasias del Recto/cirugía
18.
BMC Cancer ; 19(1): 880, 2019 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-31488078

RESUMEN

BACKGROUND: Abrogation of growth factor-dependent signaling represents an effective therapeutic strategy for patients with colorectal cancer (CRC). Here we evaluated the effectiveness of targeting the epidermal growth factor (EGF) receptors HER-2 and HER-3 in the three cell lines LS513, LS1034 and SW837. METHODS: Treatment with HER-2-specific antibodies trastuzumab and pertuzumab resulted in a mild reduction of cellular viability. In contrast, the antibody-drug conjugate T-DM1 mediated a strong and dose-dependent decrease of viability and Akt phosphorylation. RESULTS: The most striking effects were observed with the dual tyrosine kinase inhibitor lapatinib, and the Pan-ErbB inhibitor afatinib. Selectively, the effect of EGF receptor inhibition was augmented by a combination with 5-fluorouracil and oxaliplatin. Finally, high expression of HER-3 was detected in 121 of 172 locally advanced rectal cancers (70.3%). In conclusion, inhibition of EGF receptors effectively blocks downstream signaling and significantly impairs viability of CRC cells. However, the effectiveness of receptor inhibition highly depends on the inhibitors' mode of action, as targeting HER-2 alone is not sufficient. CONCLUSION: Since HER-2 and HER-3 are expressed in a relevant number of patients, targeting both receptors may represent a promising therapeutic strategy for CRC.


Asunto(s)
Neoplasias Colorrectales/metabolismo , Terapia Molecular Dirigida/métodos , Receptor ErbB-2/antagonistas & inhibidores , Receptor ErbB-3/antagonistas & inhibidores , Afatinib/farmacología , Anticuerpos Monoclonales Humanizados/farmacología , Células CACO-2 , Supervivencia Celular/efectos de los fármacos , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/patología , Quimioterapia Combinada , Fluorouracilo/farmacología , Células HCT116 , Células HT29 , Humanos , Lapatinib/farmacología , Oxaliplatino/farmacología , Inhibidores de Proteínas Quinasas/farmacología , Receptor ErbB-2/metabolismo , Receptor ErbB-3/metabolismo , Transducción de Señal/efectos de los fármacos , Trastuzumab/farmacología
19.
World J Surg Oncol ; 17(1): 224, 2019 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-31856851

RESUMEN

BACKGROUND: CREB-binding protein (CBP) and p300 represent histone acetyltransferases (HATs) and transcriptional coactivators that play essential roles in tumour initiation and progression. Both proteins are generally thought to function as tumour suppressors, although their distinct roles in colorectal cancer (CRC) remain inconsistent and ambiguous. Thus, we analysed the expression of these two HATs in human tissue samples from patients with locally advanced rectal cancer via immunohistochemistry and evaluated their potential impacts on future CRC diagnosis and treatment. METHODS: In our analysis, we included ninety-three (n = 93) patients diagnosed with adenocarcinoma in the upper third of the rectum. None of the patients received preoperative chemoradiotherapy, but the patients did undergo primary resection of the tumour within the phase II GAST-05 trial. By using H-scores, the expression of both proteins was visualised via immunohistochemistry in resected specimens from the patients. CBP and p300 expression were correlated with clinical and follow-up data. RESULTS: Our analysis showed that high expression of CBP was significantly associated with prolonged cancer-specific survival (CSS; p = 0.002). In univariate analysis, CBP was an independent prognostic parameter for CSS (p = 0.042). High nuclear CBP expression was observed in two-thirds of patients. In contrast, we could not find any significant correlation between the expression of p300 and cancer-specific survival in this cohort of patients (p = 0.09). We did not observe any cooperation between CBP and p300 in our analysis. CONCLUSIONS: High expression of CBP was significantly associated with improved oncological outcomes. This finding could help to stratify patients in the future for CRC treatment. Histone deacetylase (HDAC) inhibitors are increasingly playing a role in oncological treatment and could additionally become therapeutic options in CRC. Our findings need to be further evaluated and verified in future clinical analyses.


Asunto(s)
Adenocarcinoma/metabolismo , Adenocarcinoma/patología , Proteína de Unión a CREB/metabolismo , Proteína p300 Asociada a E1A/metabolismo , Neoplasias del Recto/metabolismo , Neoplasias del Recto/patología , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor/metabolismo , Ensayos Clínicos Fase II como Asunto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pronóstico
20.
Genes Chromosomes Cancer ; 57(3): 140-149, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29119627

RESUMEN

To understand the molecular mechanism of rectal cancer and develop markers for disease prognostication, we generated and explored a dataset from 243 rectal cancer patients by gene expression microarray analysis of cancer samples and matched controls, and SNP-arrays of germline DNA. We found that two of the loci most strongly linked with colorectal cancer (CRC) risk, 8q24 (upstream of MYC) and 18q21 (in the intron of SMAD7), as well as 20q13 (in the intron of LAMA5), are tightly associated with the prognosis of rectal cancer patients. For SNPs on 18q21 (rs12953717 and rs4464148) and 20q13 (rs4925386), alleles that correlate with higher risk for the development of CRC are associated with shorter disease free survival (DFS). However, for rs6983267 on 8q24, the low risk allele is associated with a higher risk for recurrence and metastasis after surgery, and importantly, is strongly correlated with the resistance of CRC cell lines to chemoradiotherapy (CRT). We also found that although MYC expression is dramatically increased in cancer, patients with higher levels of MYC have a better prognosis. The expression of SMAD7 is weakly correlated with DFS. Notably, the presence of the 8q24 and 18q21 SNP alleles is not correlated with expression levels of MYC and SMAD7. rs4464148, and probably rs6983267 and rs4925386, are linked with overall survival time of patients. In conclusion, we show that several CRC risk SNPs detect subpopulations of rectal cancer patients with poor prognosis, and that rs6983267 probably affects prognosis through interfering with the resistance of cancer cells to CRT.


Asunto(s)
Neoplasias Colorrectales/genética , Anciano , Alelos , Cromosomas Humanos Par 18/genética , Cromosomas Humanos Par 8/genética , Neoplasias del Colon/genética , Neoplasias Colorrectales/cirugía , Femenino , Predisposición Genética a la Enfermedad/genética , Pruebas Genéticas/métodos , Estudio de Asociación del Genoma Completo , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/genética , Polimorfismo de Nucleótido Simple/genética , Pronóstico , Neoplasias del Recto/genética , Factores de Riesgo , Proteína smad7/genética , Transcriptoma/genética
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