Project description:Kaposi's sarcoma associated herpesvirus (KSHV) causes several tumors, including primary effusion lymphoma (PEL) and Kaposi's sarcoma (KS). Cellular and viral microRNAs (miRNAs) have been shown to play important roles in regulating gene expression. A better knowledge of the miRNA-mediated pathways affected by KSHV infection is therefore important for understanding viral infection and tumor pathogenesis. In this study, we used deep sequencing to analyze miRNA and cellular mRNA expression in a cell line with latent KSHV infection (SLKK) as compared to the uninfected SLK line. This approach revealed 153 differentially expressed human miRNAs, eight of which were independently confirmed by qRT-PCR. KSHV infection led to the dysregulation of ~15% of the human miRNA pool and most of these cellular miRNAs were down-regulated, including nearly all members of the 14q32 miRNA cluster, a genomic locus linked to cancer and that is deleted in a number of PEL cell lines. Furthermore, we identified 48 miRNAs that were associated with a total of 1,117 predicted or experimentally validated target mRNAs; of these mRNAs, a majority (73%) were inversely correlated to expression changes of their respective miRNAs, suggesting miRNA-mediated silencing mechanisms were involved in a number of these alterations. Several dysregulated miRNA-mRNA pairs may facilitate KSHV infection or tumor formation, such as up-regulated miR-708-5p, associated with a decrease in pro-apoptotic caspase-2 and leukemia inhibitory factor LIF, or down-regulated miR-409-5p, associated with an increase in the p53-inhibitor MDM2. Transfection of miRNA mimics provided further evidence that changes in miRNAs are driving some observed mRNA changes. Using filtered datasets, we also identified several canonical pathways that were significantly enriched in differentially expressed miRNA-mRNA pairs, such as the epithelial-to-mesenchymal transition and the interleukin-8 signaling pathways. Overall, our data provide a more detailed understanding of KSHV latency and guide further studies of the biological significance of these changes.
Project description:This SuperSeries is composed of the SubSeries listed below. Purpose: Kaposi’s sarcoma (KS)-associated herpesvirus (KSHV) causes several lymphoproliferative disorders, including KS, a common AIDS-associated malignancy. Cellular and viral microRNAs (miRNAs) have been shown to play important roles in regulating the expression of genes in oncogenesis. Herpesviruses, including KSHV, encode for miRNAs that are involved in angiogenesis, inflammation and apoptosis. A better knowledge of the miRNA-mediated pathways that regulate KSHV infection is therefore essential for an improved understanding of viral infection and pathogenesis. Methods: In this study, we used deep sequencing to analyze miRNA, both viral and human, and mRNA expression in KS tumor-derived human cells. Results: This approach revealed 153 differentially expressed human miRNAs between KSHV-positive and -negative cells. Differential expression of eight miRNAs was independently confirmed by qRT-PCR. We additionally showed that a majority (~73%) of KSHV-regulated miRNAs are down-regulated, including most members of the 14q32 miRNA cluster. Specifically, human miR-409-3p, which is known to target the pro-angiogenic growth factor angiogenin and the inflammation marker fibrinogen-beta, was significantly down-regulated in KSHV-infected cells based on deep sequencing and qRT-PCR. Despite this substantial down-regulation of cellular miRNAs, hsa-miR-708-5p was significantly up-regulated by KSHV and has been shown to directly inhibit pro-apoptotic protease Caspase-2. Finally, we evaluated to what extent there was an inverse correlation between miRNA and mRNA expression levels. Using filtered datasets, we identified relevant canonical pathways that were significantly enriched. Conclusion: Taken together, our data demonstrate that most human miRNAs affected by KSHV are repressed and our findings highlight the relevance of studying the post-transcriptional gene regulation of miRNAs for KSHV-associated malignancies.
Project description:This SuperSeries is composed of the SubSeries listed below. Purpose: Kaposi’s sarcoma (KS)-associated herpesvirus (KSHV) causes several lymphoproliferative disorders, including KS, a common AIDS-associated malignancy. Cellular and viral microRNAs (miRNAs) have been shown to play important roles in regulating the expression of genes in oncogenesis. Herpesviruses, including KSHV, encode for miRNAs that are involved in angiogenesis, inflammation and apoptosis. A better knowledge of the miRNA-mediated pathways that regulate KSHV infection is therefore essential for an improved understanding of viral infection and pathogenesis. Methods: In this study, we used deep sequencing to analyze miRNA, both viral and human, and mRNA expression in KS tumor-derived human cells. Results: This approach revealed 153 differentially expressed human miRNAs between KSHV-positive and -negative cells. Differential expression of eight miRNAs was independently confirmed by qRT-PCR. We additionally showed that a majority (~73%) of KSHV-regulated miRNAs are down-regulated, including most members of the 14q32 miRNA cluster. Specifically, human miR-409-3p, which is known to target the pro-angiogenic growth factor angiogenin and the inflammation marker fibrinogen-beta, was significantly down-regulated in KSHV-infected cells based on deep sequencing and qRT-PCR. Despite this substantial down-regulation of cellular miRNAs, hsa-miR-708-5p was significantly up-regulated by KSHV and has been shown to directly inhibit pro-apoptotic protease Caspase-2. Finally, we evaluated to what extent there was an inverse correlation between miRNA and mRNA expression levels. Using filtered datasets, we identified relevant canonical pathways that were significantly enriched. Conclusion: Taken together, our data demonstrate that most human miRNAs affected by KSHV are repressed and our findings highlight the relevance of studying the post-transcriptional gene regulation of miRNAs for KSHV-associated malignancies.
Project description:Altered microRNA (miRNA) expression is a hallmark of many cancer types. The combined analysis of miRNA and messenger RNA (mRNA) expression profiles is crucial to identifying links between deregulated miRNAs and oncogenic pathways. Therefore, we investigated the small non-coding (snc) transcriptomes of nine clear cell renal cell carcinomas (ccRCCs) and adjacent normal tissues for alterations in miRNA expression using a publicly available small RNA-Sequencing (sRNA-Seq) raw-dataset. We constructed a network of deregulated miRNAs and a set of differentially expressed genes publicly available from an independent study to in silico determine miRNAs that contribute to clear cell renal cell carcinogenesis. From a total of 1,672 sncRNAs, 61 were differentially expressed across all ccRCC tissue samples. Several with known implications in ccRCC development, like the upregulated miR-21-5p, miR-142-5p, as well as the downregulated miR-106a-5p, miR-135a-5p, or miR-206. Additionally, novel promising candidates like miR-3065, which i.a. targets NRP2 and FLT1, were detected in this study. Interaction network analysis revealed pivotal roles for miR-106a-5p, whose loss might contribute to the upregulation of 49 target mRNAs, miR-135a-5p (32 targets), miR-206 (28 targets), miR-363-3p (22 targets), and miR-216b (13 targets). Among these targets are the angiogenesis, metastasis, and motility promoting oncogenes c-MET, VEGFA, NRP2, and FLT1, the latter two coding for VEGFA receptors.
Project description:The variant virulent porcine epidemic diarrhea virus (PEDV) strain (YN15) can cause severe porcine epidemic diarrhea (PED); however, the attenuated vaccine-like PEDV strain (YN144) can induce immunity in piglets. To investigate the differences in pathogenesis and epigenetic mechanisms between the two strains, differential expression and correlation analyses of the microRNA (miRNA) and mRNA in swine testicular (ST) cells infected with YN15, YN144, and mock were performed on three comparison groups (YN15 vs Control, YN144 vs Control, and YN15 vs YN144). The mRNA and miRNA expression profiles were obtained using next-generation sequencing (NGS), and the differentially expressed (DE) (p-value < 0.05) mRNA and miRNA were obtained using DESeq R package. mRNAs targeted by DE miRNAs were predicted using the miRanda algortithm. 8039, 8631 and 3310 DE mRNAs, and 36, 36, and 22 DE miRNAs were identified in the three comparison groups, respectively. 14,140, 15,367 and 3771 DE miRNA-mRNA (targeted by DE miRNAs) interaction pairs with negatively correlated expression patterns were identified, and interaction networks were constructed using Cytoscape. Six DE miRNAs and six DE mRNAs were randomly selected to verify the sequencing data by real-time relative quantitative reverse transcription polymerase chain reaction (qRT-PCR). Based on bioinformatics analysis, we discovered the differences were mostly involved in host immune responses and viral pathogenicity, including NF-κB signaling pathway and bacterial invasion of epithelial cells, etc. This is the first comprehensive comparison of DE miRNA-mRNA pairs in YN15 and YN144 infection in vitro, which could provide novel strategies for the prevention and control of PED.
Project description:Using next-generation sequencing to decipher the molecular mechanisms underlying aberrant rheumatoid arthritis synovial fibroblasts (RASF) activation, we performed transcriptome-wide RNA-seq and small RNA-seq on synovial fibroblasts from rheumatoid arthritis (RA) subject and normal donor. Differential expression of mRNA and miRNA was integrated with interaction analysis, functional annotation, regulatory network mapping and experimentally verified miRNA-target interaction data, further validated with microarray expression profiles. In this study, 3049 upregulated mRNA and 3552 downregulated mRNA, together with 50 upregulated miRNA and 35 downregulated miRNA in RASF were identified. Interaction analysis highlighted contribution of miRNA to altered transcriptome. Functional annotation revealed metabolic deregulation and oncogenic signatures of RASF. Regulatory network mapping identified downregulated FOXO1 as master transcription factor resulting in altered transcriptome of RASF. Differential expression in three miRNA and corresponding targets (hsa-miR-31-5p:WASF3, hsa-miR-132-3p:RB1, hsa-miR-29c-3p:COL1A1) were also validated. The interactions of these three miRNA-target genes were experimentally validated with past literature. Our transcriptomic and miRNA interactomic investigation identified gene signatures associated with RASF and revealed the involvement of transcription factors and miRNA in an altered transcriptome. These findings help facilitate our understanding of RA with the hope of serving as a springboard for further discoveries relating to the disease.
Project description:Neurodegenerative diseases encompass a wide variety of pathological conditions caused by a loss of neurons in the central nervous system (CNS) and are severely debilitating. Exosome contains bio-signatures of great diagnostic and therapeutic value. There is proof that exosomal proteins can be biomarkers for Alzheimer's disease (AD) and Parkinson's disease (PD). MicroRNAs in exosome has potential to be an important source of biomarkers for neurodegenerative diseases. Here, we report exosomal microRNA performance of human plasma in neurodegenerative diseases by small RNA sequencing. A wide range of altered exo-miRNA expression levels were detected in both AD and PD patients. Down-regulated miRNAs in AD samples were enriched in ECM-receptor interaction pathway and both up-/down-regulated miRNAs in PD samples were enriched in fatty acid biosynthesis pathway. Compared to the control, 8 miRNAs were found to be significantly elevated/declined in AD and PD samples, of which 4 miRNAs were newly identified. Additionally, two exosome isolating methods were compared and the reproducibility of plasma exo-miRNA expression was confirmed, suggesting the feasibility of large-scale clinical application of this method. This study revealed exo-miRNA expression levels in neurodegenerative diseases, proposed new biomarkers and their potential functional pathway for AD and PD, confirmed the reproductivity of exo-miRNA profiles by using a different exosome isolating method, and compared the results with plasma miRNA expression. Therefore, this study also provides a precedent for identifying exosomal biomarkers of neurodegenerative diseases in plasma by high-throughput sequencing and it could extend the therapeutic repertoire of exosomal biomarkers.
Project description:MicroRNAs (miRNAs) are small non-coding RNAs that mediate gene expression at the post-transcriptional and translational levels by an imperfect binding to target mRNA 3'UTR regions. While the ab-initio computational prediction of miRNA-mRNA interactions still poses significant challenges, it is possible to overcome some of its limitations by carefully integrating into the analysis the paired expression profiles of miRNAs and mRNAs. In this work, we show how the choice of a proper probe annotation for microarray platforms is an essential requirement to achieve good sensitivity in the identification of miRNA-mRNA interactions. We compare the results obtained from the analysis of the same expression profiles using both gene and transcript based custom CDFs that we have developed for a number of different annotations (ENSEMBL, RefSeq, AceView). In all cases, transcript-based annotations clearly improve the effectiveness of data integration and thus provide a more reliable confirmation of computationally predicted miRNA-mRNA interactions.