Project description:In order to define the targets of two miRNA overexpressed in NK cells in CFS/ME paitents, miRNA precursors for hsa-miR-99b and hsa-miR-330-3p were transfected in to buffy coat derived Natural Killer cells isolated by negative magnetic selection.
Project description:Chronic Fatigue Syndrome (CFS/ME) is a complex multisystem disease, with a pathogenesis that is undetermined. A large cohort of genes demonstrating altered expression in CFS/ME implicates the role of translational regulatory molecules, microRNA (miRNA), in the pathogenesis of this disease. We aimed to define the changes in microRNA expression in peripheral blood mononuclear cell (PBMC) samples in CFS/ME patients. miRNA expression was analysed in PBMC samples taken from CFS/ME patients and healthy controls, using the Ambion Bioarray V1. miRNA demonstrating differential expression were validated by qRT-PCR and analysed in an independent patient cohort in fractionated blood cell populations. The targets of miRNA hsa-miR-99b and hsa-miR-330-3p were then identified by gene expression analysis after transfection into primary NK cells.Microarray analysis identified differential expression of 34 miRNA, all of which were up-regulated. Four of the 34 miRNA had confirmed expression changes by qRT-PCR. Fractionating PBMC samples by cell type from an independent patient cohort identified changes in miRNA expression in NK-cells, B-cells and monocytes with the most significant abnormalities occurring in NK cells. Transfecting primary NK cells with hsa-miR-99b and hsa-miR-330-3p, respectively, resulted in gene expression changes consistent with NK cell activation and diminished cytotoxicity.This study demonstrates altered microRNA expression in the peripheral blood mononuclear cells of CFS/ME patients, which are potential diagnostic biomarkers. The greatest degree of miRNA deregulation was identified in NK cells with targets consistent with cellular activation and altered effector function.
Project description:MiRNAs have been shown to alter both protein expression and secretion in different cellular contexts. By combining in vitro, in vivo and in silico techniques, we demonstrated that overexpression of pre-miR-1307 reduced the ability of breast cancer cells to induce endothelial cell sprouting and angiogenesis. However, the molecular mechanism behind this and the effect of the individual mature miRNAs derived from pre-miR-1307 on protein secretion and is largely unknown. Here, we overexpressed miR-1307-3p|0, -3p|1 and 5p|0 in MDA-MB-231 breast cancer cells and assessed the impact of miRNA overexpression on protein secretion by Mass Spectrometry. Unsupervised hierarchical clustering revealed a distinct phenotype induced by overexpression of miR-1307-5p|0 compared to the controls and to the 5’isomiRs derived from the 3p-arm. Together, our results suggest different impacts of miR-1307-3p and miR-1307-5p on protein secretion which is in line with our in vitro observation that miR-1307-5p, but not the isomiRs derived from the 3p-arm reduce endothelial cell sprouting in vitro. Hence these data support the hypothesis that miR-1307-5p is at least partly responsible for impaired vasculature in tumors overexpressing pre-miR-1307.
Project description:Oxaliplatin (oxPt) resistance in colorectal cancers (CRC) is a major unsolved problem. Consequently, predictive markers and a better understanding of resistance mechanisms are urgently needed. To investigate if the recently identified predictive miR-625-3p is functionally involved in oxPt resistance, stable and inducible models of miR-625-3p dysregulation were analyzed. Ectopic expression of miR-625-3p in CRC cells led to increased resistance towards oxPt. The mitogen-activated protein kinase (MAPK) kinase 6 (MAP2K6/MKK6) – an activator of p38 MAPK - was identified as a functional target of miR-625-3p, and, in agreement, was down-regulated in patients not responding to oxPt therapy. The miR-625-3p resistance phenotype could be reversed by anti-miR-625-3p treatment and by ectopic expression of a miR-625-3p insensitive MAP2K6 variant. Transcriptome, proteome and phosphoproteome profiles revealed inactivation of MAP2K6-p38 signaling as a possible driving force behind oxPt resistance. We conclude that miR-625-3p induces oxPt resistance by abrogating MAP2K6-p38 regulated apoptosis and cell cycle control networks.
Project description:Friedreich’s ataxia (FRDA; OMIM 229300), an autosomal recessive neurodegenerative mitochondrial disease, is the most prevalent hereditary ataxia. In addition, FRDA patients showed additional non-neurological features such as scoliosis, diabetes and cardiac complications. Hypertrophic cardiomyopathy, which is found in two thirds of patients at the time of diagnosis, is the primary cause of death in these patients. In this data set, using small RNA-sequencing of small RNA purified from plasma samples of FRDA patients and controls we identified differential expression of miRNAs (hsa-miR-128-3p, hsa-miR-625-3p, hsa-miR-130b-5p, hsa-miR-151a-5p, hsa-miR-330-3p, hsa-miR-323a-3p, and hsa-miR-142-3p) between both groups. In addition, we found that miR-323a-3p can be used as a biomarker for differentiation of FRDA patients with cardiac problems. Identification of miRNA signatures could therefore provide new molecular explanation for pathological mechanisms occurring during the natural history of the FRDA. Since miRNA levels change with disease progression and pharmacological interventions, miRNAs will contribute to design new therapeutic strategies and improve clinical decisions. Plama miRNA profiles of 25 Friedreich's ataxia patients and 17 healthy subjects were generated by deep sequencing using Illumina HiScan SQ.
Project description:Friedreich’s ataxia (FRDA; OMIM 229300), an autosomal recessive neurodegenerative mitochondrial disease, is the most prevalent hereditary ataxia. In addition, FRDA patients showed additional non-neurological features such as scoliosis, diabetes and cardiac complications. Hypertrophic cardiomyopathy, which is found in two thirds of patients at the time of diagnosis, is the primary cause of death in these patients. In this data set, using small RNA-sequencing of small RNA purified from plasma samples of FRDA patients and controls we identified differential expression of miRNAs (hsa-miR-128-3p, hsa-miR-625-3p, hsa-miR-130b-5p, hsa-miR-151a-5p, hsa-miR-330-3p, hsa-miR-323a-3p, and hsa-miR-142-3p) between both groups. In addition, we found that miR-323a-3p can be used as a biomarker for differentiation of FRDA patients with cardiac problems. Identification of miRNA signatures could therefore provide new molecular explanation for pathological mechanisms occurring during the natural history of the FRDA. Since miRNA levels change with disease progression and pharmacological interventions, miRNAs will contribute to design new therapeutic strategies and improve clinical decisions.
Project description:Overexpression of miR-127-3p in LN229 glioblastoma cells promotes their migration and invasion in vitro and in vivo in xenograft models. We used microarrays to detail the global programme of gene expression in miR-127-3p overexpression LN229 cells compared with mock overexpression LN229 cells MiR-127-3p overexpression LN229 cells and and mock overexpression LN229 cells were cultured in DMEM cell culture media for RNA extraction and hybridization on Affymetrix microarrays. We sought to obtain the genes regulated by miR-127-3p in glioblastoma cell lines.
Project description:Long non-coding RNAs (lncRNAs) play pivotal roles in diseases such as osteoarthritis (OA). However, knowledge of the biological roles of lncRNAs is limited in OA. We aimed to explore the biological function and molecular mechanism of HOTTIP in chondrogenesis and cartilage degradation. We used the human mesenchymal stem cell (MSC) model of chondrogenesis, in parallel with, tissue biopsies from normal and OA cartilage to detect HOTTIP, CCL3, and miR-455-3p expression in vitro. Biological interactions between HOTTIP and miR-455-3p were determined by RNA silencing and overexpression in vitro. We evaluated the effect of HOTTIP on chondrogenesis and degeneration, and its regulation of miR-455-3p via competing endogenous RNA (ceRNA). Our in vitro ceRNA findings were further confirmed within animal models in vivo. Mechanisms of ceRNAs were determined by bioinformatic analysis, a luciferase reporter system, RNA pull-down, and RNA immunoprecipitation (RIP) assays. We found reduced miR-455-3p expression and significantly upregulated lncRNA HOTTIP and CCL3 expression in OA cartilage tissues and chondrocytes. The expression of HOTTIP and CCL3 was increased in chondrocytes treated with interleukin-1β (IL-1β) in vitro. Knockdown of HOTTIP promoted cartilage-specific gene expression and suppressed CCL3. Conversely, HOTTIP overexpression reduced cartilage-specific genes and increased CCL3. Notably, HOTTIP negatively regulated miR-455-3p and increased CCL3 levels in human primary chondrocytes. Mechanistic investigations indicated that HOTTIP functioned as ceRNA for miR-455-3p enhanced CCL3 expression. Taken together, the ceRNA regulatory network of HOTTIP/miR-455-3p/CCL3 plays a critical role in OA pathogenesis and suggests HOTTIP is a potential target in OA therapy.
Project description:In the current study, we characterized the global miRNA expression profile in mouse pancreatic acinar cells during acute pancreatitis using next-generation RNA-Sequencing. We identified 330 known and 6 novel miRNAs being expressed in mouse pancreatic acinar cells. At basal state, miR-148a-3p, miR-375-3p, miR-217-5p, miR-216a-5p were among the most abundantly expressed whereas miR-24-5p and miR-421-3p were least abundant. Treatment of acinar cells with supra-maximal caerulein or bile acid induced numerous changes in miRNA expression levels. In particular, we observed significant upregulation of miR-21-3p in these experiments, which was further, confirmed using mouse models of acute pancreatitis. In summary, this is the first comprehensive analysis of miRNA expression in healthy mouse pancreatic acinar cells and how this expression signature changes in acute pancreatitis.
Project description:RNA-seq on Kelly neuroblastoma cells transfected with the following miRNA: non-targeting scrambled control, miR-99b-5p, miR-380-3p, miR-485-3p, miR-100-3p, miR-1915-3p, miR-1283