394 research outputs found

    RASSF1A promoter methylation and expression analysis in normal and neoplastic kidney indicates a role in early tumorigenesis

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    <p>Abstract</p> <p>Background</p> <p>Epigenetic silencing of the RAS association domain family 1A (<it>RASSF1A</it>) tumor suppressor gene promoter has been demonstrated in renal cell carcinoma (RCC) as a result of promoter hypermethylation. Contradictory results have been reported for <it>RASSF1A </it>methylation in normal kidney, thus it is not clear whether a significant difference between <it>RASSF1A </it>methylation in normal and tumor cells of the kidney exists. Moreover, RASSF1A expression has not been characterized in tumors or normal tissue as yet.</p> <p>Results</p> <p>Using combined bisulfite restriction analysis (COBRA) we compared RASSF1A methylation in 90 paired tissue samples obtained from primary kidney tumors and corresponding normal tissue. Bisulfite sequence analysis was carried out using both pooled amplicons from the tumor and normal tissue groups and subclones obtained from a single tissue pair. Expression of RASSF1A was analyzed by the use of tissue arrays and immunohistochemistry. We found significantly increased methylation in tumor samples (mean methylation, 20%) compared to corresponding normal tissues (mean methylation, 11%; <it>P </it>< 0.001). Densely methylated sequences were found both in pooled and individual sequences of normal tissue. Immunohistochemical analysis revealed a significant reduced expression of RASSF1A in most of the tumor samples. Heterogeneous expression patterns of RASSF1A were detected in a subgroup of histologically normal tubular epithelia.</p> <p>Conclusion</p> <p>Our methylation and expression data support the hypothesis that <it>RASSF1A </it>is involved in early tumorigenesis of renal cell carcinoma.</p

    Editorial: Massive Open Online Courses und ihre Rolle in der digitalen (Hochschul-)Lehre

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    Massive Open Online Courses, kurz MOOCs, sind Online-Kurse mit einer großen Zahl an Teilnehmer:innen, die zumeist auf speziellen Plattformen kostenlos zur Verfügung gestellt werden. Mit dem Kurs zur Künstlichen Intelligenz von Sebastian Thrun mit über 160.000 Lernenden fanden MOOCs zunehmend Verbreitung. Spätestens seit der COVID19-Pandemie sind sie nicht mehr aus unserem universitären Hochschulalltag wegzudenken und heute zum Teil integraler Bestandteil von Lehrveranstaltungen. Durch vielfältige Einsatzmöglichkeiten werden so Weiterbildungen, Workshops oder joint lectures unterstützt. Das aktuelle Themenheft rief zu Beiträgen rund um MOOCs auf und erlaubt dadurch einen Einblick in die facettenreichen Entwicklungen. In der aktuellen Ausgabe finden Sie hierzu spannende Beiträge mit Erfahrungsberichten, neuesten Erkenntnissen, Weiterentwicklungen und didaktischen Einsatzmöglichkeiten. Wir laden Sie also herzlich ein, mit uns gemeinsam dieses innovative, zukunftsträchtige und auch nachhaltige Thema weiter zu vertiefen

    Divergent functions and distinct localization of the Notch ligands DLL1 and DLL3 in vivo

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    The Notch ligands Dll1 and Dll3 are coexpressed in the presomitic mesoderm of mouse embryos. Despite their coexpression, mutations in Dll1 and Dll3 cause strikingly different defects. To determine if there is any functional equivalence, we replaced Dll1 with Dll3 in mice. Dll3 does not compensate for Dll1; DLL1 activates Notch in Drosophila wing discs, but DLL3 does not. We do not observe evidence for antagonism between DLL1 and DLL3, or repression of Notch activity in mice or Drosophila. In vitro analyses show that differences in various domains of DLL1 and DLL3 individually contribute to their biochemical nonequivalence. In contrast to endogenous DLL1 located on the surface of presomitic mesoderm cells, we find endogenous DLL3 predominantly in the Golgi apparatus. Our data demonstrate distinct in vivo functions for DLL1 and DLL3. They suggest that DLL3 does not antagonize DLL1 in the presomitic mesoderm and warrant further analyses of potential physiological functions of DLL3 in the Golgi network

    Fibronectin 1 mRNA expression correlates with advanced disease in renal cancer

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    <p>Abstract</p> <p>Background</p> <p>Fibronectin 1 (<it>FN1</it>) is a glycoprotein involved in cellular adhesion and migration processes. The aim of this study was to elucidate the role of <it>FN1 </it>in development of renal cell cancer (RCC) and to determine a prognostic relevance for optimal clinical management.</p> <p>Methods</p> <p>212 renal tissue samples (109 RCC, 86 corresponding tissues from adjacent normal renal tissue and 17 oncocytomas) were collected from patients undergoing surgery for renal tumors and subjected to total RNA extraction. Detection of <it>FN1 </it>mRNA expression was performed using quantitative real time PCR, three endogenous controls, renal proximal tubular epithelial cells (RPTEC) as biological control and the ΔΔCt method for calculation of relative quantities.</p> <p>Results</p> <p>Mean tissue specific <it>FN1 </it>mRNA expression was found to be increased approximately seven fold comparing RCC and corresponding kidney control tissues (p < 0.001; ANOVA). Furthermore, tissue specific mean <it>FN1 </it>expression was increased approx. 11 fold in clear cell compared to papillary RCC (p = 9×10<sup>-5</sup>; Wilcoxon rank sum test). Patients with advanced disease had higher <it>FN1 </it>expression when compared to organ-confined disease (p < 0.001; Wilcoxon rank sum test). Applying subgroup analysis we found a significantly higher <it>FN1 </it>mRNA expression between organ-confined and advanced disease in the papillary and not in the clear cell RCC group (p = 0.02 vs. p = 0.2; Wilcoxon rank sum test). There was an increased expression in RCC compared to oncocytoma (p = 0.016; ANOVA).</p> <p>Conclusions</p> <p>To our knowledge, this is the first study to show that <it>FN1 </it>mRNA expression is higher in RCC compared to normal renal tissue. <it>FN1 </it>mRNA expression might serve as a marker for RCC aggressiveness, indicating early systemic progression particularly for patients with papillary RCC.</p

    Scale Up Multilingualism in Health Emergency Learning : Developing an Automated Transcription and Translation Tool

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    World Health Organization's (WHO) emergency learning platform OpenWHO provided by Hasso Plattner Institut (HPI) delivered online learning in real-time and in multiple languages during the COVID-19 pandemic. The challenge was to move from manual transcription and translation to automated to increase the speed and quantity of materials and languages available. TransPipe tool was introduced to facilitate this task. We describe the TransPipe development, analyze its functioning and report key results achieved. TransPipe successfully connects existing services and provides a suitable workflow to create and maintain video subtitles in different languages. By the end of 2022, the tool transcribed nearly 4,700 minutes of video content and translated 1,050,700 characters of video subtitles. Automated transcription and translation have enormous potential as a public health learning tool, allowing the near-simultaneous availability of video subtitles on OpenWHO in many languages, thus improving the usability of the learning materials in multiple languages for wider audiences.publishedVersionPeer reviewe

    Metastandard für den internationalen Austausch von MOOCs – der MOOChub als erster Prototyp

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    Der MOOChub ist eine Webseite, die weit über 700 Massive Open Online Courses (MOOCs) aus dem deutschsprachigen Raum von insgesamt neun unterschiedlichen Partner:innen listet. Damit eine solche Seite automatisiert aufgebaut werden kann, ist es notwendig, dass alle Partner:innen die Metadaten der Kurse in gleicher Weise beschreiben und verfügbar machen. Dieser Artikel beschreibt zunächst die Entstehung der Idee eines gemeinsamen Standards und wie dieser im Anschluss entwickelt worden ist. Das Ergebnis ist einerseits ein offen lizenzierter Quasi-Standard, der sich an üblichen Standards orientiert, und ein erster Prototyp, der sogenannte MOOChub, auf dem nun alle Kurse auffindbar und durchsuchbar sind. Abschließend wird über die nächsten möglichen und auch notwendigen Entwicklungen berichtet, die die Schnittstelle weiter optimieren sollen

    miRNA-target network reveals miR-124as a key miRNA contributing to clear cell renal cell carcinoma aggressive behaviour by targeting CAV1 and FLOT1

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    Clear cell renal cell carcinoma (ccRCC) is an aggressive tumor with frequent metastatic rate and poor survival. Integrated analyses allow understanding the interplay between different levels of molecular alterations.We integrated miRNA and gene expression data from 458 ccRCC and 254 normal kidney specimens to construct a miRNA-target interaction network.We identified the downregulated miR-124-3p, -30a-5p and -200c-3p as the most influential miRNAs in RCC pathogenesis.miR-124-3p and miR-200c-3p expression showed association with patient survival, miR-30a-5p was downregulated in metastases compared to primary tumors. We used an independent set of 87 matched samples for validation. We confirmed the functional impact of these miRNAs by in vitro assays. Restoration of these miRNAs reduced migration, invasion and proliferation. miR-124-3p decreased the S phase of cell cycle, as well. We compared transcriptome profiling before and after miRNA overexpression, and validated CAV1 and FLOT1 as miR-124-3p targets. Patients with higher CAV1 and FLOT1 had lower miR-124-3p expression and shorter overall survival.We hypothesize that these three miRNAs are fundamental contributing to ccRCC aggressive/metastatic behavior; and miR-124-3p especially has a key role through regulating CAV1 and FLOT1 expression. Restoration of the levels of these miRNAs could be considered as a potential therapeutic strategy for ccRCC
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