Analysis of the miRNA profile associated with c-Src-mediated transformation
ABSTRACT: To address the molecular mechanisms underlying c-Src-mediated tumor progression, we previously developed a model system using Csk-deficient fibroblasts that can be transformed by wild-type c-Src. In this study, we applied this system for the analysis of the potential contribution of miRNA to c-Src-mediated transformation. Pair-wise significance analysis of the microarray indicated that seven miR genes were significantly upregulated and six miRNA genes were downregulated in c-Src-transformed cells with a P value below 0.01 and with a fold change over 2.0. Csk-/- mouse embryonic fibroblasts (Csk-/- MEFs) were transfected with empty vector, c-Src, Csk/c-Src, or Csk. Each sample was run in duplicate.
Project description:Chromatin modifying activities for construction of appropriate epigenetic landscapes by polycomb repressive complex 2 (PRC2) play an essential role in development and tumorigenesis. However, the spatiotemporal mechanisms by which PRC2 achieves diverse epigenomes for specific tissue or cellular contexts remain poorly understood. Here, we discovered that LATS2 knockout causes dysregulation of PRC2 and subsequent transcriptome changes for differentiation in both mouse and human cells. LATS2 depletion dependent dysregulation of PRC2 also effects H3K4me3 and forms negative feedback loop for maintenance of PRC2. Further analyses reveal that LATS2 on chromatin binds to EZH2 and LATS2 has ability to phosphorylate PRC2 in vitro. These LATS2 dependent H3K27me3 targets are highly induced during neurogenesis, and statistical analysis of glioblastoma multiforme reveals that LATS2-high cases show more dedifferentiated transcriptome and poor prognosis with silencing of H3K27me3 targets. These observations suggest that LATS2-mediated epigenome coordination is pivotal for development and disease, including cancer. The rabeled cRNAs from Lats2-/- mouse embryonic fibroblasts (MEFs) and litter wild type MEFs were subjected to Agilent Mouse miRNA Microarray 8 x 15K. Each sample was run in biological dupulicate (different PDL).
Project description:Viral infections affecting the upper or lower respiratory tract induce mucin production in the epithelial surfaces of the respiratory cells. However, a little is known about how mucins are produced on the surfaces of respiratory epithelial cells and affects viral replication. In the course of the investigation of the cellular responses in the early stage of Influenza A virus (IAV) infection, we found that two miRNAs, miR-221 and miR-17-3p, which target the mRNA of GalNAc transferase 3 (GALNT3), are rapidly down-regulated as early as 1.5 h post-infection. To understand the early host cell responses to the IAV infection, we performed miRNA microarray analysis using a human alveolar adenocarcinoma cell line, A549 cells, infected with influenza A/Puerto Rico/8/34 H1N1 (PR8) virus. We isolated the cellular RNAs at 0.5, 1.5 and 4.5 h post-infection and detected significant changes in the global profile of miRNA expression after infection with IAV. mouse embryonic fibroblasts. Each sample was run in duplicate.
Project description:In the present study we evaluated the miRNA expression profile of 31 high risk, stage 4 neuroblastoma patients. We compared miRNA expression profiles of 14 long-survivors (alive with an overall survival time > 36 months) and 17 short-survivors (dead of disease within 36 months from diagnosis. Deaths due to toxicity were censored).
Project description:To explore functionally crucial tumor-suppressive (TS)-miRNAs in hepatocellular carcinoma (HCC), we performed integrative function- and expression-based screenings of TS-miRNAs in six HCC cell lines. The screenings identified seven miRNAs, which showed growth-suppressive activities through the overexpression of each miRNA and were endogenously downregulated in HCC cell lines. Further expression analyses using a large panel of HCC cell lines and primary tumors demonstrated four miRNAs, miR-101, -195, -378 and -497, as candidate TS-miRNAs frequently silenced in HCCs. Among them, two clustered miRNAs miR-195 and miR-497 showed significant growth-suppressive activity with induction of G1 arrest. Comprehensive exploration of their targets using Argonute2-immunoprecipitation-deep-sequencing (Ago2-IP-seq) and genome-wide expression profiling after their overexpression, successfully identified a set of cell-cycle regulators, including CCNE1, CDC25A, CCND3, CDK4, and BTRC. Our results suggest the molecular pathway regulating cell cycle progression to be integrally altered by downregulation of miR-195 and miR-497 expression, leading to aberrant cell proliferation in hepatocarcinogenesis. Analysis of miRNA profile change in the Ago2-IP fraction after overexpression with miR-195 or miR-497 miRNA expression analysis using Immunopreticipated RNA fractions with anti-human-Argonute 2 antibody for non-treated, miR-195 or miR-497 overexpressed Hep G2 cell.
Project description:MicroRNAs (miRNAs) are an evolutionarily conserved large class of small non-coding RNAs that mediate post-transcriptional silencing of genes and influence a broad spectrum of biological processes ranging from embryonic development to organismal death. Our previous study identified the miR-29 family, three paralogous species of miR-29a/b/c, as the most predominantly expressed small RNA in aged mouse brain compared to neonate one. The mouse brain miR-29 is highly astrocytic. Its expression is quiescent during early brain development, and thereafter steadily increases to a saturating level around the end of the reproductive phase. To explore the functional relevance of miR-29 expression to the neural physiology of mouse brain from the mechanistic perspective of mammalian species-specific lifespan, we here designed a gain-of-function approach through forced expression of miR-29 in astrocyte from mouse fetus and surveyed the resulting alteration in the transcriptional and translational levels. DNA microarray analyses retrieved a total of 5,589 genes showing a temporal significant expression changes in the miR-29-transfected fetal astrocytes, and classified them into two gene groups positively or negatively regulated by miR-29. Mass spectrometry (MS)-based quantification of translational products of miR-29-responsive genes identified 18 species of miR-29 target candidates. We performed functional enrichment analyses using bioinformatics resources to elucidate the biological roles of the gene sets thus identified, and obtained their expression trend that favor the processes for facilitating cell differentiation while supporting normal cell proliferation /survival, which was different from the functional signatures of miR-29 at adult stages, implying the bifunctional property of miR-29 depending on the developmental context. Our present results strongly suggest that miR-29 serves as the central coordinator to shift the global gene expression in the developing mouse brain toward matured phenotype, and through which ensure the programmed transition to the post-developmental stage that is inherently set for the mouse lifespan. DNA microarray experiment: Sample labeling, hybridization and washing were performed following the standard protocol detailed in the Agilent One-Color Microarray-Based Gene Expression Analysis ver.5.7. Briefly, a One-color Spike-Mix was diluted 1000-fold and a 5-μl aliquot of the diluted mix were added to every 0.5 μg of total RNA samples (three each of extraction replicates of miR-29-treated sample and control sample named elsewhere) prior to labeling reaction. The labeling reaction was carried out separately for the RNA samples using a Quick Amp Labeling Kit one-color, in the presence of cyanine 3-CTP. The dye-labeled target (1.6 μg as cRNA) was fragmented and hybridized on an Agilent Whole Mouse Genome 4X44K microarray at 65°C for 17 hr with a Gene Expression Hybridization Kit. The hybridized slide was washed in Gene Expression Wash Buffer 1 at room temperature for 1 min, which was followed by a wash for 1 min in Gene Expression Wash Buffer 2. The processed microarrays were scanned using an Agilent DNA Microarray Scanner. Data extraction from raw image files was done with Agilent Feature Extraction software ver.10.7.
Project description:We performed a PCR array of 84 ECM-related genes using RNA obtained from dermal fibroblasts stimulated with or without EBI3. 18 of the 84 genes were upregulated and 22 genes were downregulated in EBI3-treated fibroblasts in comparison with untreated cells. In the present study, we examined the involvement of the IL-12 family cytokines in the expression of the extracellular matrix.
Project description:We investigated the changes in gene expression profile between subconfluent (80%) and overconfluent HT-1080 fibrosarcoma cell line. We have employed whole genome microarray expression profiling as a discovery platform to identify genes expression profiles in HT-1080 cells. Total RNAs from subconfluent (HT-1080_80%) and overconfluent (HT-1080_overconfluent) HT-1080 cells were harvested and subjected to the microarray analysis.
Project description:Given previous works showing that, in the process of adipogenic differentiation of 3T3-L1 fibroblasts, the cells need to be cultured to confluency followed by additional incubation before initiating differentiation, we hypothesized that contact inhibition of proliferation (CIP) is requisite for making the cells prone to the differentiation. We screened upregulated genes in contact-inhibited 3T3-L1 fibroblasts, as well as NIH3T3 fibroblasts that are also sensitive to contact inhibition, by a whole genome microarray analysis. We also screened the genes that undergo rapid downregulation after the initiation of adipogenic differentiation. To investigate the mechanism of contact inhibition of proliferation and adipogenic differentiation of 3T3-L1 and NIH3T3 fibroblasts, we have employed whole genome microarray expression profiling as a discovery platform to identify genes with the potential to distinguish proliferating and contact-inhibited cells and cells that undergo adipogenic differentiation. Total RNAs from 80% confluent (3T3-L1_80%, NIH3T3_80%) and overconfluent (3T3-L1_overconfluent, NIH3T3_overconfluent) cells and cells stimulated with the adipogenic differentiation medium (ZenBio) for 2 hours (3T3-L1_adipo diff med 2 hours, NIH3T3_adipo diff med 2 hours) were harvested and subjected to the microarray analysis.
Project description:Lincomycin is a lincosamide antibiotic that forms cross-links within the peptidyl transferase loop region of the 23S rRNA of the 50S subunit of the bacterial ribosome, thereby inhibiting protein synthesis. We have previously reported that lincomycin at concentrations below the minimum inhibitory concentration potentiates the production of secondary metabolites in actinomycete strains. We aimed to elucidate the fundamental mechanisms underlying lincomycin induction of secondary metabolism in actinomycetes. Therefore, the dose-dependent response of lincomycin on gene expression of the model actinomycetes Streptomyces coelicolor A3(2) and possible relationships to secondary metabolism have been investigated.
Project description:The aim of this study was to investigate the effects of administration of carbon black nanoparticle (CB-NP) to pregnant mice on the development of lymphoid tissues in infantile mice. Pregnant ICR mice were treated with a suspension of CB-NP 95 microg/kg/time) by intranasal instillation, twice, on gestational day 5 and 9. Spleen and thymus were collected from offspring mice at 5 days post-partum. RNA sample was taken from spleen of 5-day-old mouse prenatally received carbon black nanoparticle, while control RNA was taken from control counterpart prenatally received distilled water. Comparisons among groups were made by one-color method with normalized data from Cy3 channels for data analysis.