Reprogramming of somatic cells produces induced pluripotent stem cells (iPSCs) that are invaluable resources for biomedical research. Transcriptional and epigenetic changes have been investigated to facilitate our understanding of the reprogramming process. Here, we extended the previous transcriptome studies by performing RNA-seq on cells defined by a combination of multiple cellular surface markers. We found that transcriptome changes during early reprogramming occur independently from the opening of closed chromatin by OCT4, SOX2, KLF4 and MYC (OSKM). Furthermore, our data identify multiple spliced forms of genes uniquely expressed at each progressive stage of reprogramming. In particular, we found a pluripotency-specific spliced form of CCNE1 that significantly enhances reprogramming. In addition, single nucleotide polymorphism (SNP) expression analysis reveals that monoallelic gene expression is induced in the intermediate stages of reprogramming while biallelic expression is recovered upon completion of reprogramming. Our transcriptome data provide unique opportunities in understanding human iPSC reprogramming. Overall design: RNA samples from intermediates of hiPSC reprogramming were obtained. Gene expression of those cells were analyzed.
Transcriptome Signature and Regulation in Human Somatic Cell Reprogramming.
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View SamplesReprogramming to pluripotency after overexpression of OCT4, SOX2, KLF4 and MYC is accompanied by global genomic and epigenomic changes. Histone modification and DNA methylation states in iPSCs have been shown to be highly similar with embryonic stem cells (ESCs). However, epigenetic differences still exist between iPSCs and ESCs. In particular, aberrant DNA methylation states found in iPSCs are a major concern for using iPSCs in a clinical setting. Thus, it is critical to find factors that regulate DNA methylation states in reprogramming. Here, we found that the miR-29 family is an important epigenetic regulator during human somatic cell reprogramming. Our global DNA methylation and hydroxymethylation analysis shows that DNA demethylation is a major event mediated by miR-29a depletion during early reprogramming, and that iPSCs derived from miR-29a depletion are epigenetically closer to ESCs. Our findings uncover an important miRNA-based approach to generate clinically robust iPSCs. Overall design: Bisulphite converted gDNAs of D551 fibroblasts transduced for 3 days with overexpression of DNMTs, TETs, TDG and OSKM or miR29a/b/c and control sponge were hybridized into Illumina Infinium HumanMethylation 450K Beadchip.
Regulation of the DNA Methylation Landscape in Human Somatic Cell Reprogramming by the miR-29 Family.
Specimen part, Treatment, Subject
View SamplesEpidemiology studies have linked exposure to pollutant particles to increased cardiovascular mortality and morbidity, however, the mechanism remains unknown. In this study, we hypothesized that the ultrafine fraction of ambient pollutant particles would cause endothelial cells dysfunction. We profiled gene expression of human pulmonary artery endothelial cells (HPAEC) exposed to ultrafine Chapel Hill particles (UFP) (100g/ml) or vehicle for 4h with Affymetrix HG U133 Plus 2.0 chips (N = 4 each). Using an unpaired t-test (p <0.01, 5% false discovery rate) we found 426 unique genes to be differentially expressed with 320 upregulated genes and 106 downregulated genes. Among these genes, we noted upregulation of genes related to coagulation-inflammation circuitry including tissue factor (F3), coagulation factor II receptor-like 2 (F2RL2, PAR3), interleukin (IL)-6 and IL-8. Upregulation of these genes were independently confirmed by RT-PCR and/or protein release. Genes related to the CXC chemokine family that have been implicated in the pathogenesis of vascular disease were upregulated, including MCP-1 (2.60 fold), IL-8 (2.47 fold), CXCL1 (1.41 fold), CXCL2 (1.95 fold), CXCL3 (2.28 fold) and CXCR4 (1.30 fold). In addition, genes related to clotting independent signaling of F3 were also differentially expressed, including FOS, JUN and NFKBIA. Treatment of HPAEC with UFP for 16 hours increased the release of IL6 and IL8 by 1.9-fold and 1.8-fold respectively. Pretreatment of HPAEC with a blocking antibody against F3 attenuated IL6 and IL8 release by 30% and 70% respectively. Thus using gene profiling, we uncovered that UFP may induce vascular endothelial cells to express genes related to clotting and angiogenesis. These results provide a novel hypothesis that PM may cause cardiovascular adverse health effects via induction of tissue factor in vascular endothelial cells which then triggers clotting dependent and independent downstream signaling.
Up-regulation of tissue factor in human pulmonary artery endothelial cells after ultrafine particle exposure.
Treatment
View SamplesTransformation of follicular lymphoma (FL) to a more aggressive disease is associated with rapid progression and death. Existing molecular markers for transformation are few and their clinical impact is limited. Here, we report on a whole-genome study of DNA copy numbers and gene expression profiles in serial FL biopsies. We identified 698 genes with high correlation between gene expression and copy number and the molecular network most enriched for these cis-associated genes. This network includes 14 cis-associated genes directly related to the NFB pathway. For each of these 14 genes, the correlated NFB target genes were identified and corresponding expression scores defined. The scores for six of the cis-associated NFB pathway genes (BTK, IGBP1, IRAK1, ROCK1, TMED7-TICAM2 and TRIM37) were significantly associated with transformation. The results suggest that genes regulating B-cell survival and activation are involved in transformation of FL
Whole-genome integrative analysis reveals expression signatures predicting transformation in follicular lymphoma.
Specimen part
View SamplesTranscription factor Stat5 is constitutively active in human prostate cancer but not in normal prostate epithelium. Stat5 activation is associated with prostate cancer lesions of high histological grades, and is present in the majority of castration-resistant recurrent human prostate cancers. The molecular mechnisms underlying constitutive activation of Stat5 in primary and recurrent human prostate cancer are currently unclear.
Stat5 promotes metastatic behavior of human prostate cancer cells in vitro and in vivo.
Specimen part, Cell line
View SamplesStat5a and Stat5b proteins are highly homologous with greater than 90% amino acid identity and share binding to the palindromic Stat5 consensus sequence, TTCNNNGAA, but individual roles of each transcription factor in breast cancer have not been thoroughly evaluated. To determine the degree of similarity between transcripts modulated by Stat5a and Stat5b proteins in human breast cancer, we utilized genome-wide transcript profiling to identify genes regulated specifically by Stat5a or Stat5b in response to prolactin.
Low levels of Stat5a protein in breast cancer are associated with tumor progression and unfavorable clinical outcomes.
Cell line
View SamplesMitochondrial DNA (mtDNA) mutations are maternally inherited and are associated with a broad range of debilitating and fatal diseases. Assisted reproductive technologies designed to uncouple the inheritance of mtDNA from nuclear DNA may enable women who carry mtDNA mutations to have a genetically related child with a greatly reduced risk of disease. Here we report for the first time that pronuclear transplantation (PNT) between normally fertilised human zygotes provides an effective approach to preventing transmission of mtDNA disease. We found that the procedures previously used to perform PNT between abnormally fertilized human zygotes are highly inefficient when applied to those that undergo normal fertilization. We have therefore developed an alternative approach based on transplanting PN shortly after completion of the second meiotic division rather than shortly before onset of the first mitosis. This approach promotes highly efficient development to the blastocyst stage without affecting nuclear genome integrity. Furthermore, the expression profile of genes encoded by the nuclear and mitochondrial genomes was indistinguishable from unmanipulated control embryos. Importantly, levels of mtDNA transferred with the nuclear genome are below the threshold for mtDNA disease. Together these data indicate that transplantation of pronuclei early in the first cell cycle holds promise as a safe and effective approach to preventing transmission of mtDNA disease. Overall design: Single-Cell RNA-seq analysis of embryos generated by pronuclear transfer and unmanipulated control embryos The relationship between single cell samples and the embryo from which they were derived is indicated in the sample ''characteristics: sample type'' field.
Towards clinical application of pronuclear transfer to prevent mitochondrial DNA disease.
No sample metadata fields
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