唾液腺腺样囊性癌中相关微小RNAs及其靶基因的生物信息学分析

目的 探讨唾液腺腺样囊性癌(SACC)潜在的微小RNAs(miRNAs)分子标志物,构建miRNA-mRNA调控网络,并阐明其潜在的分子机制.方法 从Gene Expression Omnibus(GEO)数据库下载2个SACC的微阵列芯片数据,通过R语言进行分析差异的miRNAs与mRNA.应用FunRich 3.1...     

Integrated analysis of the molecular mechanisms in idiopathic pulmonary fibrosis

Rationale: Idiopathic pulmonary fibrosis (IPF) is one of the most aggressive forms of idiopathic interstitial pneumonia. Some miRNAs may be associated with IPF and may affect the occurrence and development of IPF in various pathways. Many miRNAs and genes that may be involved in the development of IPF have been discovered using chip and high throughput technologies.Methods: We analyzed one miRNA and four mRNA databases. We identified hub genes and pathways related to IPF using GO, KEGG enrichment analysis, gene set variation analysis (GSVA), PPI network construction, and hub gene analysis. A comprehensive analysis of differentially expressed miRNAs (DEMs), predicted miRNA target genes, and differentially expressed genes (DEGs) led to the creation of a miRNA-mRNA regulatory network in IPF.Results: We found 203 DEGs and 165 DEMs that were associated with IPF. The findings of enrichment analyses showed that these DEGs were mainly involved in antimicrobial humoral response, antimicrobial humoral immune response mediated by antimicrobial peptide, extracellular matrix organization, cell killing, and organ or tissue specific immune response. The VEGFA, CDH5, and WNT3A genes overlapped between hub genes and the miRNA-mRNA regulatory network. The miRNAs including miR-199b-5p, miR-140-5p, miR-199a-5p, miR-125A-5p, and miR-107 that we predicted would regulate the VEGFA, CDH5, and WNT3A genes, which were also associated with IPF or other fibrosis-related diseases. GSVA indicated that metabolic processes of UTP and IMP, immune response, regulation of Th2 cell cytokine production, and positive regulation of NK cell-mediated immunity are associated with the pathogenesis and treatment of IPF. These pathways also interact with VEGFA, CDH5, and WNT3A.Conclusion: These findings provide a new research direction for the diagnosis and treatment of IPF.     

Systematic identification of microRNA and messenger RNA profiles in hepatitis C virus-infected human hepatoma cells

In order to investigate the global and dynamic host microRNAs (miRNAs)/messenger RNAs (mRNAs) expression alteration during in vitro acute HCV infection, a comprehensive microarray analysis was performed using human hepatoma cells. Totally, 108 human miRNAs and 1247 mRNAs were identified whose expression levels changed for more than 2.0-fold in response to HCV infection. Upon HCV infection, signature from the unique miRNA expression pattern reflected the involvement of miRNA-regulated host cellular physiology and antiviral mechanism, whereas a preponderance of differentially regulated genes associated with metabolism, cell growth, apoptosis and cytokine/chemokine pathways. Furthermore, a reverse regulatory association of differentially expressed miRNAs and their predicted targets was constructed. Finally, the differentially expressed miRNAs such as miR-24, miR-149?, miR-638 and miR-1181 were identified to be involved in HCV entry, replication and propagation. These results suggest that combined miRNA and mRNA profiling may have superior potential as a diagnostic and mechanistic feature in HCV infection.     

基于 TCGA 数据库筛选、 分析并验证宫颈癌生物标志物

目的 基于生物信息学筛选分析宫颈癌差异表达基因 ( differentially expressed gene, DEGs) 及差 异表达 miRNA, 并进一步对差异基因和蛋白进行验证, 以期寻找潜在的生物标志物和治疗靶点。 方法 从 肿瘤基因组图谱 (the cancer genome atlas, TCGA) 数据库获取宫颈癌相关数据, edgeR 算法筛选 DEGs 和差 异 miRNAs。 利用 Cytoscape3. 8. 2 软件构建 mRNA-miRNA 共表达网络。 利用 DAVID 软件对 DEGs 和通过 miRWalk 网站预测的差异 miRNA 的目标基因进行 GO 富集分析和 KEGG 富集分析。 利用 qPCR 和 Western 印 迹技术对 DEGs 进行进一步验证。 结果 筛选出 149 个上调的 DEGs 和 171 个下调的 DEGs, 以及 46 个上调 的差异 miRNAs 和 64 个下调的差异 miRNAs。 DEGs 和 miRNA 目标基因在细胞组成上的富集具有一致性, 都富集在胞质、 核和核质中。 但共表达网络发现 DEGs 和差异 miRNAs 之间不存在明显的调控关系。 因此, 后续实验重点放在了对 DEGs 的验证上, 对差异表达性较为显著的 TCEAL6、 CLEC3B、 LMOD1、 CNN1 进行 了验证。 qPCR 显示它们在宫颈癌中表达量均显著降低, 符合预期, 对 CNN1 进行的 Western 印迹也显示其 在宫颈癌中的低表达。 结论 TCEAL6、 CLEC3B、 LMOD1、 CNN1 在宫颈癌中均显著低表达, 有望成为宫颈 癌生物标志物。     

基于转录组测序分析微重力环境下MC3T3-E1成骨细胞miRNA/mRNA表达谱及功能变化

目的探讨微重力环境对MC3T3-E1成骨细胞分化的影响。方法采用转录组测序技术(RNA-seq)观察微重力培养前后MC3T3-E1成骨细胞miRNA/mRNA表达谱变化,测序结果采用q-PCR验证。采用生物信息学方法进一步研究差异性表达的miRNA/mRNA。结果与对照组(CON)相比,模拟微重力组(SMG)共有160条miRNA和1 912个mRNAs发生显著改变;根据生物信息学结果,筛选出10个关键性基因(3条miRNA、7个mRNA),其中miR-9_6666-5p为微重力敏感miRNA,可能在微重力环境下成骨细胞分化过程中起到重要的作用。结论在微重力环境下,成骨细胞分化受到抑制可能与miRNA/mRNA表达谱的改变有关。研究结果将有助于深入理解miRNA与mRNA在微重力环境下调控成骨分化与骨生成的分子机制。     

Investigation of microRNA expression signatures in HCC via microRNA Gene Chip and bioinformatics analysis

BackgroundDysregulation of miRNAs is closely involved with hepatocellular carcinoma (HCC) progression, oncogenesis and signalling pathways. The aim of this study was to investigate differences in expression of miRNAs in HCC tissue in comparison to healthy liver tissue, as well as to explore the key miRNA-targeted genes.MethodsGene Chip microarray analysis was used to analyse differentially expressed miRNAs (DEMs) in tissues, and qRT-PCR was performed to validate the top 9 downregulated miRNAs. Gene Ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes pathway (KEGG) enrichment analyses were performed for target genes using the DAVID database. A protein-protein interaction (PPI) network of the target genes was created by STRING and visualised using Cytoscape. Three online miRNA databases were utilised to aid in the prediction of genes targeted by the top 10 significantly altered DEMs.ResultsIn total, 153 upregulated and 206 downregulated miRNAs were identified in HCC tissue. The genes targeted by the top 10 increased and decreased miRNAs were 6 and 1060, respectively. Moreover, FOXO1 was projected to be regulated by all twenty miRNAs. A PPI network was constructed that consisted of 956 nodes and 1298 edges. Four significant modules, consisting of 66 hub genes, were detected from the PPI system via MCODE. Functional enrichment demonstrated that miRNAs have a vital function in cancer development and advancement.ConclusionIn summary, our study identified DEMs in HCC tissue, major target genes and possible molecular mechanisms that underlie HCC, providing novel insights for treatment approaches.     

Deep sequencing of small RNAs from human skin reveals major alterations in the psoriasis miRNAome

Psoriasis is a chronic and complex inflammatory skin disease with lesions displaying dramatically altered mRNA expression profiles. However, much less is known about the expression of small RNAs. Here, we describe a comprehensive analysis of the normal and psoriatic skin miRNAome with next-generation sequencing in a large patient cohort. We generated 6.7 × 10(8) small RNA reads representing 717 known and 284 putative novel microRNAs (miRNAs). We also observed widespread expression of isomiRs and miRNA*s derived from known and novel miRNA loci, and a low frequency of miRNA editing in normal and psoriatic skin. The expression and processing of selected novel miRNAs were confirmed with qRT-PCR in skin and other human tissues or cell lines. Eighty known and 18 novel miRNAs were 2-42-fold differentially expressed in psoriatic skin. Of particular significance was the 2.7-fold upregulation of a validated novel miRNA derived from the antisense strand of the miR-203 locus, which plays a role in epithelial differentiation. Other differentially expressed miRNAs included hematopoietic-specific miRNAs such as miR-142-3p and miR-223/223*, and angiogenic miRNAs such as miR-21, miR-378, miR-100 and miR-31, which was the most highly upregulated miRNA in psoriatic skin. The functions of these miRNAs are consistent with the inflammatory and hyperproliferative phenotype of psoriatic lesions. In situ hybridization of differentially expressed miRNAs revealed stratified epidermal expression of an uncharacterized keratinocyte-derived miRNA, miR-135b, as well as the epidermal infiltration of the hematopoietic-specific miRNA, miR-142-3p, in psoriatic lesions. This study lays a critical framework for functional characterization of miRNAs in healthy and diseased skin.     

MicroRNA Expression Profiles in Thyroid Tumors

MicroRNAs (miRNAs) constitute a recently identified class of small endogenous noncoding RNAs that act as negative regulators of the protein-coding gene expression and may impact cell differentiation, proliferation and survival, i.e., all fundamental cellular processes implicated in carcinogenesis. miRNA expression is deregulated in many types of human cancers, including thyroid cancer. The purpose of this review is to summarize the existing findings of miRNA deregulation in thyroid tumors and its potential role in thyroid cancer biology and molecular diagnostics.     

miRNA与肿瘤的研究进展

微小RNA(microRNA, miRNA)是一种长度约为22 nt的非编码RNA,它们通过miRNA介导的特异性的基因沉默导致靶mRNA降解及抑制蛋白质的合成调控转录后基因表达水平。miRNA对细胞的增殖、分化和凋亡有重要的调节作用,在正常组织和肿瘤组织中的表达显著不同,参与了肿瘤的发生、发展。本文主要讨论miRNA在肿瘤方面的研究进展。     

Computational identification of hepatitis E virus-encoded microRNAs and their targets in human

microRNAs (miRNAs) are small, noncoding RNAs which regulate eukaryotic gene expression via RNA interference pathway. Recently, miRNAs have been identified in a number of viruses with current evidence suggesting that they regulate gene expression in both virus and host. This makes viral miRNAs potential targets of clinical intervention, with the possibility of inhibiting aberrant host gene expression associated with the disease. In this study, computational approaches were taken to scan the hepatitis E virus (HEV) genome for putative pre-miRNA molecules, which were then analyzed for the presence of mature miRNAs. The 3′-untranslated region (3′-UTR) and 5′-UTR sequences targeted by these miRNAs were identified using Miranda computational tool, followed by the functional annotation of the associated messenger RNAs (mRNAs) using Gene Ontology terms and Kyoto Encyclopaedia of Genes and Genomes pathway analysis. We identified a total of nine viral encoded miRNAs in HEV. After functional annotation, the majority of the viral miRNA targets were found to be associated with cell cycle, cell differentiation, nitrogen compound metabolism, transmembrane transport, and chromosome organization. This in-silico study identified putative viral miRNAs encoded by HEV and their potential human mRNAs targets. These viral miRNAs have the potential to affect host gene expression as well as viral life cycle and pathogenesis and can, therefore, serve as potential therapeutic targets during HEV infection.     

MicroRNA expression pattern of undifferentiated and differentiated human embryonic stem cells

Many of the currently established human embryonic stem (hES) cell lines have been characterized extensively in terms of their gene expression profiles and genetic stability in culture. Recent studies have indicated that microRNAs (miRNAs), a class of noncoding small RNAs that participate in the regulation of gene expression, may play a key role in stem cell self-renewal and differentiation. Using both microarrays and quantitative PCR, we report here the differences in miRNA expression between undifferentiated hES cells and their corresponding differentiated cells that underwent differentiation in vitro over a period of 2 weeks. Our results confirm the identity of a signature miRNA profile in pluripotent cells, comprising a small subset of differentially expressed miRNAs in hES cells. Examining both mRNA and miRNA profiles under multiple conditions using cross-correlation, we find clusters of miRNAs grouped with specific, biologically interpretable mRNAs. We identify patterns of expression in the progression from hES cells to differentiated cells that suggest a role for selected miRNAs in maintenance of the undifferentiated, pluripotent state. Profiling of the hES cell "miRNA-ome" provides an insight into molecules that control cellular differentiation and maintenance of the pluripotent state, findings that have broad implications in development, homeostasis, and human disease states.     

microRNA的组织特异性表达及其检测方法

microRNA（miRNA）是一类调节基因表达的非编码的小RNA。miRNA参与细胞的分化、增殖及凋亡等多种生命活动,并与多种疾病的发生和发展密切相关。miRNA表达存在组织特异性,而疾病（包括肿瘤）的发生和发展也表现为某些miRNA的表达失调。miRNA相关研究均需检测细胞的miRNA表达水平,常用杂交和RT—PCR等方法检测。     

microRNA在固有免疫调控中作用的研究进展

microRNA(miRNA)是一类内源性的短链非编码RNA分子,能与特定的信使RNA靶向结合,在转录后水平调控基因表达.miRNA可在多个环节参与调控机体固有免疫反应.微生物感染时,miRNA可通过调控模式识别受体信号通路及产生的细胞因子,负性或正性调控固有免疫应答.在病毒感染时,宿主编码的miRNA能抑制病毒复制,...     

MicroRNAs and colon and rectal cancer: differential expression by tumor location and subtype

MicroRNAs are thought to have an impact on cell proliferation, apoptosis, stress responses, maintenance of stem cell potency, and metabolism and are, therefore, important in the carcinogenic process. In this study, we examined 40 colon tumors, 30 rectal tumors, and 30 normal tissue samples (10 proximal colon, 10 distal colon, and 10 rectal paired with cancer cases) to examine miRNA expression profiles in colon and rectal tumors. MiRNA expression levels were adjusted for multiple comparisons; tumor tissue was compared with noncancerous tissue from the same site. A comparison of normal tissue showed 287 unique miRNAs that were significantly differentially expressed at the 1.5-fold level and 73 with over a two-fold difference in expression between colon and rectal tissue. Examination of miRNAs that were significantly differentially expressed at the 1.5-fold level by tumor phenotype showed 143 unique miRNAs differentially expression for microsatellite instability positive (MSI+) colon tumors; 129 unique miRNAs differentially expressed for CpG Island Methylator Phenotype positive (CIMP+) colon tumors; 135 miRNAs were differentially expressed for KRAS2-mutated colon tumors, and 139 miRNAs were differentially expressed for TP53-mutated colon tumors. Similar numbers of differentially expressed miRNAs were observed for rectal tumors, although the miRNAs differentially expressed differed. There were 129 unique miRNAs for CIMP+, 143 unique miRNAs for KRAS2-mutated, and 136 unique miRNAs for TP53-mutated rectal tumors. These results suggest the importance of miRNAs in colorectal cancer and the need for studies that can confirm these results and provide insight into the diet, lifestyle, and genetic factors that influence miRNA expression.     

RIP-chip-SRM--a new combinatorial large-scale approach identifies a set of translationally regulated bantam/miR-58 targets in C. elegans

MicroRNAs (miRNAs) are small, noncoding RNAs that negatively regulate gene expression. As miRNAs are involved in a wide range of biological processes and diseases, much effort has been invested in identifying their mRNA targets. Here, we present a novel combinatorial approach, RIP-chip-SRM (RNA-binding protein immunopurification + microarray + targeted protein quantification via selected reaction monitoring), to identify de novo high-confidence miRNA targets in the nematode Caenorhabditis elegans. We used differential RIP-chip analysis of miRNA-induced silencing complexes from wild-type and miRNA mutant animals, followed by quantitative targeted proteomics via selected reaction monitoring to identify and validate mRNA targets of the C. elegans bantam homolog miR-58. Comparison of total mRNA and protein abundance changes in mir-58 mutant and wild-type animals indicated that the direct bantam/miR-58 targets identified here are mainly regulated at the level of protein abundance, not mRNA stability.