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Inhibition of HER Receptors Reveals Distinct Mechanisms of Compensatory Upregulation of Other HER Family Members: Basis for Acquired Resistance and for Combination TherapyGutsch, Daniela, Jenke, Robert, Büch, Thomas, Aigner, Achim 03 May 2023 (has links)
Overexpression of members of the HER/erbB transmembrane tyrosine kinase family like HER2/erbB2/neu is associated with various cancers. Some heterodimers, especially HER2/HER3 heterodimers, are particularly potent inducers of oncogenic signaling. Still, from a clinical viewpoint their inhibition has yielded only moderate success so far, despite promising data from cell cultures. This suggests acquired resistance upon inhibitor therapy as one putative issue, requiring further studies in cell culture also aiming at rational combination therapies. In this paper, we demonstrate in ovarian carcinoma cells that the RNAi-mediated single knockdown of HER2 or HER3 leads to the rapid counter-upregulation of the respective other HER family member, thus providing a rational basis for combinatorial inhibition. Concomitantly, combined knockdown of HER2/HER3 exerts stronger anti-tumor effects as compared to single inhibition. In a tumor cell line xenograft mouse model, therapeutic intervention with nanoscale complexes based on polyethylenimine (PEI) for siRNA delivery, again reveals HER3 upregulation upon HER2 single knockdown and a therapeutic benefit from combination therapy. On the mechanistic side, we demonstrate that HER2 knockdown or inhibition reduces miR-143 levels with subsequent de-repression of HER3 expression, and validates HER3 as a direct target of miR-143. HER3 knockdown or inhibition, in turn, increases HER2 expression through the upregulation of the transcriptional regulator SATB1. These counter-upregulation processes of HER family members are thus based on distinct molecular mechanisms and may provide the basis for the rational combination of inhibitors.
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Targets of Hsa-miR-488* In Human Prostate Carcinoma CellsSlaibi, Jinani Elias 08 June 2010 (has links)
No description available.
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Finding Song Melody Similarities Using a DNA String Matching AlgorithmFrey, Jeffrey Daniel 23 April 2008 (has links)
No description available.
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NANOPARTICLE DRUG DELIVERY SYSTEMS FOR CANCER THERAPYYung, Bryant Chinung January 2014 (has links)
No description available.
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Investigating the Biological and Molecular Consequences of MiR-9 Dysregulation in Canine Mast Cell Tumors and OsteosarcomaFenger, Joelle M. 20 May 2015 (has links)
No description available.
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Cross-Talk Between Epigenetic Regulation And Mir-17~92 Cluster Expression In Idiopathic Pulmonary Fibrosis (IPF)Dakhlallah, Duaa 18 March 2011 (has links)
No description available.
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The Biological Functions of miR-122 and its Therapeutic Application in Liver CancerHsu, Shu-hao 25 June 2012 (has links)
No description available.
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Beat Tracking of Jazz Instruments : Performance of Beat Tracking Algorithms on Jazz Drums and Double-BassSvanström, Oskar, Gustafsson, Linnéa January 2022 (has links)
Beat tracking is a common research area within music information retrieval (MIR). Jazz is a musical genre that is commonly rich in rhythmical complexity, which makes beat tracking challenging. The aim of this study is to analyze how well beat tracking algorithms detect the beats of jazz instruments. In this study, drums and double-bass were recorded in an ensemble but on single tracks. Three modern beat tracking algorithms were examined: LibRosa Dynamic, Essentia Multi-Feature, and madmom RNN. The algorithms’ beat trackings were evaluated using common metrics: the F-measure, P-score and Cemgil accuracy. The results showed that bass tracks generally got consistent results from all algorithms. However, all algorithms struggled with octave errors (the detected number of beats is off by a factor of two) and off-beats. When music was played without restrictions to the beat rhythm, madmom RNN generally performed the best, which suggests that machine learning with RNN (recurrent neural networks) is a good approach for beat tracking on rhythmically complex tracks. / Beat tracking är ett vanligt område inom music information retrieval (MIR). Jazz är en musikgenre som ofta är rytmisk komplex, vilket kan göra beat tracking utmanande. Denna studies syfte är att analysera hur väl beat tracking-algoritmer detekterar taktslagen hos jazzinstrument. I denna studie spelades trummor och kontrabas in samtidigt, men på separata spår. Tre moderna algoritmer för beat tracking undersöktes: LibRosa Dynamic, Essentia Multi-Feature, samt madmom RNN. Algoritmernas taktslagsestimeringar utvärderades utifrån vanligen tillämpade mätetal: F-measure, P-score och Cemgil accuracy. Resultaten visade att basspåren generellt sett gav konsekventa resultat från alla algoritmer. Däremot fick alla algoritmer oktavfel (antalet detekterade beats är fel med en faktor två) och off-beats. När musiken framfördes utan restriktioner i spelade taktslag presterade madmom RNN generellt bäst. Detta pekar mot att maskininlärning med RNN (recurrent neural networks) är en bra metod för beat tracking av rytmiskt komplexa spår.
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The Biochemical Basis of The miR-21 Expression by The Mu-Opioid ReceptorChang, Jen-Kuan January 2015 (has links)
Opioid receptors are members of the superfamily of seven transmembrane G protein-coupled receptors (GPCRs) which share several structural and functional characteristics. There are 3 subtypes of opioid receptors, designated μ (MOR), δ (DOR), and κ (KOR) opioid receptors, have been found in the immune, nervous, gastrointestinal and other tissues. We have attempted to clarify the nature of MOR-induced signal transduction pathways in leukocytes. We found that the activation of MOR leads to a significant induction of ERK phosphorylation in peripheral blood mononuclear cells from normal donors using the MOR-selective agonist DAMGO. We are also interested in determining the role of this signaling pathway in the regulation of the immune response. Recent experiments using selective inhibitors suggests that the activation of ERK involves a pathway composed of Raf, Ras, and MEK1/2 kinases, but is independent of PI3 kinase. After treatment of multiple protein kinase inhibitors we found the PKC inhibitor Go-6983 and PLC inhibitor U73122 could also inhibit ERK phosphorylation in MOR stable line (HEK-MOR). According to the results from the Go-6983 and H-89 inhibitor treatment experiments, we found PKCμ/PKD1, a family member of Protein Kinase D, may be involved in MOR-induced ERK phosphorylation. We also found PKCμ/PKD1 S916 phosphorylation after MOR activation and the PKCμ specific inhibitor CID755673 inhibited the MOR-mediated ERK activation. ERK phosphorylation activated several transcription factors in human monocytes, the activation of transcription factors has been proved to induce miRNA expression. We have initiated a series of experiments to study the regulation of miRNA expression by MOR in human monocytes. We found miR-21, miR-155, miR-29a, miR-20b expression were significantly up-regulated following morphine treatment, and morphine-induced miR-21 expression is down-regulated following pretreatment with the ERK inhibitor U0126 and PKD inhibitor CID755673 in human primary monocytes. The results suggest that morphine-induced MOR activation results in up-regulation of miRNA expression human monocytes and this may regulate monocyte and/or macrophage function thought PKCμ/Ras/Raf/ERK signaling pathway. / Molecular Biology and Genetics
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MicroRNA Expression in Regulatory T Cells in Chronic Obstructive Pulmonary DiseaseChatila, Wissam M. F. January 2015 (has links)
COPD is characterized by an abnormal regulatory T cell (Treg) response with a shift towards a Th1 and Th17 cell responses. However, it is unclear if the function of Treg cells is impaired by smoking and in COPD. In addition, the miRNA profile of Treg cells in COPD is unknown and whether miRNA deregulation contributes to COPD immunopathogenesis. We set the objective to study Treg cell function isolated from peripheral blood of patients with COPD versus controls and to compare their miRNA profiles. We also were interested in exploring the function of some of the differentially expressed Treg cell miRNAs. We assessed the Treg cell function by observing their suppressive activity on autologous effector T cells and analyzed their miRNA expression initially by microarray analysis then conducted real time RT-PCR validation for selected miRNAs. In Silico target gene analysis for the validated miRNAs suggested that miR-199-5p is particularly relevant to Treg cell physiology so its function was investigated further using CCD-986Sk and MOLT-4 cells. We found no difference in Treg cell function between COPD and controls but we were able to identify 6 and 96 miRNAs that were differentially expressed in COPD versus control Treg cells. We confirmed that miR-199a-5p was repressed by approximately 4 fold in Treg cells of COPD patients compared to cells in healthy smokers. Importantly, miR-199a-5p had significant overrepresentation of its target genes in the Treg cell transcriptome, with many targets associated with the TGF-b activation pathway. We also confirmed the function of miR-199a5p in an in-vitro loss-of-function cell model running TaqMan® arrays of the Human TGF-b Pathway. These findings suggest that the abnormal repression of miR-199a-5p in patients with COPD compared to unaffected smokers may be involved in modulating the adaptive immune balance in favor of a Th1 and Th17 response. / Microbiology and Immunology
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