It has been difficult to elucidate the structure of gene regulatory networks under anticancer drug treatment. Here, we developed an algorithm to highlight the hub genes that play a major role in creating the upstream and downstream relationships within a given set of differentially expressed genes. The directionality of the relationships between genes was defined using information from comprehensive collections of transcriptome profiles after gene knockdown and overexpression. As expected, among the drug-perturbed genes, our algorithm tended to derive plausible hub genes, such as transcription factors. Our validation experiments successfully showed the anticipated activity of certain hub gene in establishing the gene regulatory network that was associated with cell growth inhibition. Notably, giving such top priority to the hub gene was not achieved by ranking fold change in expression and by the conventional gene set enrichment analysis of drug-induced transcriptome data. Thus, our data-driven approach can facilitate to understand drug-induced gene regulatory networks for finding potential functional genes.
InDePTH: detection of hub genes for developing gene expression networks under anticancer drug treatment.
Cell line, Treatment
View SamplesIn order to characterize the differences between second trimester Down syndrome (DS) and euploid fetuses, we compared gene expression in uncultured amniotic fluid supernatant samples. We identified individually differentially expressed genes via paired t-tests in the matched samples, and a set of differentially expressed genes on chromosome 21 using Gene Set Enrichment Analysis. Functional pathway analysis of the resulting genes highlighted the importance of oxidative stress, ion transport, and G-protein signaling in the DS fetuses.
Functional genomic analysis of amniotic fluid cell-free mRNA suggests that oxidative stress is significant in Down syndrome fetuses.
Sex, Specimen part
View SamplesMitochondria can be involved in regulating cellular stress response to hypoxia and tumor growth, but little is known about that mechanistic relationship. Here, we show that mitochondrial deficiency severely retards tumor xenograft growth with impairing hypoxic induction of HIF-1 transcriptional activity. Using mtDNA-deficient rho0 cells, we found that HIF-1 pathway activation was comparable in slow-growing rho0 xenografts and rapid-growing parental xenografts. Interestingly, we found that ex vivo rho0 cells derived from rho0 xenografts exhibited slightly increased HIF-1alpha expression and modest HIF-1 pathway activation regardless of oxygen concentration. Surprisingly, rho0 cells, as well as parental cells treated with oxidative phosphorylation inhibitors, were unable to boost HIF-1 transcriptional activity during hypoxia, although HIF-1alpha protein levels were ordinarily increased in these cells under hypoxic conditions. These findings indicate that mitochondrial deficiency causes loss of hypoxia-induced HIF-1 transcriptional activity and thereby might lead to a constitutive HIF-1 pathway activation as a cellular adaptation mechanism in tumor microenvironment.
Mitochondrial deficiency impairs hypoxic induction of HIF-1 transcriptional activity and retards tumor growth.
Cell line
View SamplesAlterations in chromatin modifications, including DNA methylation and histone modification patterns, have been characterized under exposure of several environmental pollutants, including nickel. As with other carcinogenic metals, the mutagenic potential of nickel compounds is low and is not well correlated with its carcinogenic effects. Nickel exposure, however, is associated with alterations in chromatin modifications and related transcriptional programs, suggesting an alternative pathway whereby nickel exposure can lead to disease. To investigate the extent to which nickel exposure disrupts chromatin patterns, we profiled several histone modifications, including H3K4me3, H3K9ac, H3K27me3 and H3K9me2 as well as the insulator binding protein CTCF and the transcriptomes of control BEAS-2B cells and cells treated with nickel for 72 hours. Our results show significant alterations of the repressive histone modification H3K9me2 in nickel-exposed cells with spreading of H3K9me2 into new domains associated with gene silencing. We furthermore show that local regions of active chromatin can protect genes from nickel-induced H3K9me2 spreading. Interestingly, we show that nickel exposure selectively disrupts weaker CTCF sites, leading to spreading of H3K9me2 at these regions. These results have major implications in the understanding of how environmental carcinogens can affect chromatin dynamics and the consequences of chromatin domain disruption in disease progression. Overall design: Treat BEAS-2B cells with NiCl2 for 72 hours and compare histone modification, CTCF binding to control BEAS-2B cells to see how they regulated gene expression by RNA-seq
Epigenetic dysregulation by nickel through repressive chromatin domain disruption.
No sample metadata fields
View SamplesEndothelial cell (EC) therapy may promote vascular growth or reendothelization in a variety of disease conditions. However, the production of a cell therapy preparation containing differentiated, dividing cells presenting typical EC phenotype, functional properties and chemokine profile is challenging. We focused on comparative analysis of seven small molecule-mediated differentiation protocols of ECs from human induced pluripotent stem cells. Differentiated cells showed a typical surface antigen pattern of ECs as characterized with flow cytometry analysis, functional properties, such as tube formation and ability to uptake acetylated LDL. Gene expression analysis by RNA sequencing revealed an efficient silencing of pluripotency genes and upregulation of genes related to cellular adhesion during differentiation. In addition, distinct patterns of transcription factor expression were identified during cellular reprogramming providing targets for more effective differentiation protocols in the future. Altogether, our results suggest that the most optimal EC differentiation protocol includes early inhibition of Rho-associated coiled-coil kinase and activation of cyclic adenosine monophosphate signaling, and inhibition of transforming growth factor beta signaling after mesodermal stage. These findings provide the first systematic characterization of the most potent signalling factors and small molecules used to generate ECs from human induced pluripotent stem cells. Consequently, this work improves the existing EC differentiation protocols and opens up new avenues for controlling cell fate for regenerative EC therapy. Overall design: Comparison of the effects of signalling factors and small molecules on endothelial cell differentiation from induced pluripotent stem cells using RNA-Seq. Following small molecules and growth factors were used in different combinations and time courses: 10 uM TGFß-inhibitor SB431542, 10 uM ROCK-inhibitor Y-27632, 20 ng/ml recombinant human BMP-4 and 0,25 mM 8-Br-cAMP. In all groups without TGFß-inhibitor at day 1 in the differentiation, it was added at day 4. In those groups with BMP-4 at day 1, it was removed at day 4. Differentiating ECs were passaged every 4-6 days using Accutase.
Temporal Dynamics of Gene Expression During Endothelial Cell Differentiation From Human iPS Cells: A Comparison Study of Signalling Factors and Small Molecules.
Specimen part, Cell line, Subject
View SamplesThe level of trypsin-2 has been shown to correlate with the malignancy and metastatic potential of many cancer.
Trypsin-2 enhances carcinoma invasion by processing tight junctions and activating ProMT1-MMP.
Specimen part, Cell line
View SamplesBergmann glial cells of the vertebrate cerebellum play essential roles in the development and maintenance of cerebellar structure and function. During development, Bergmann glia provide structural support to the expanding cerebellar anlage and also serve as guides for migrating neurons (granule cells). As the cerebellum matures, Bergmann glia become important in dendritic arborization, synapse maintenance and synaptic function. The molecular mechanisms underlying these diverse and important functions of Bergmann glia remain largely unknown.
Identification of novel glial genes by single-cell transcriptional profiling of Bergmann glial cells from mouse cerebellum.
Specimen part
View SamplesTumor-specific alternative splicing is implicated in the progression of cancer, including clear cell renal cell carcinoma (ccRCC). Using ccRCC RNA-sequencing data from The Cancer Genome Atlas, we found that epithelial splicing regulatory protein 2 (ESRP2), one of the key regulators of alternative splicing in epithelial cells, is expressed in ccRCC. ESRP2 mRNA expression did not correlate with the overall survival rate of ccRCC patients, but the expression of some ESRP-target exons correlated with the good prognosis and with the expression of Arkadia (also known as RNF111) in ccRCC. Arkadia physically interacted with ESRP2, induced polyubiquitination, and modulated its splicing function. Arkadia and ESRP2 suppressed ccRCC tumor growth in a coordinated manner. Lower expression of Arkadia correlated with advanced tumor stages and poor outcomes in ccRCC patients. This study thus reveals a novel tumor-suppressive role of the Arkadia-ESRP2 axis in ccRCC. Overall design: Expression of mRNA in a ccRCC cell line OS-RC-2 under the knockdown of Arkadia or ESRP2. Knock-down of ESRP2 was confirmed by RT-PCR because of low expression of ESRP2 which resulted in non-quantitative FPKM value.
The Arkadia-ESRP2 axis suppresses tumor progression: analyses in clear-cell renal cell carcinoma.
No sample metadata fields
View SamplesWe evaluated the role of Arkadia and ESRP2 in HEK293T cells Overall design: Expression of mRNA in HEK293T cells under the knockdown of Arkadia or ESRP2
The Arkadia-ESRP2 axis suppresses tumor progression: analyses in clear-cell renal cell carcinoma.
No sample metadata fields
View SamplesThis study analysed the transcriptome of mouse Rex1GFPd2 cells before and during early differentiation and further investigated the transcriptomic changes of Nprl2 and Tsc2 knockout. Overall design: RNA samples were collected before differentiation, and on day 1, 2, 3 of differentiation; RNA samples of Rex1GFP positive population were collected for Nprl2, Tsc2 knockout and compared to wild type cells.
Genome-wide CRISPR-KO Screen Uncovers mTORC1-Mediated Gsk3 Regulation in Naive Pluripotency Maintenance and Dissolution.
Specimen part, Cell line, Subject
View Samples