Data on the temporal dynamics of human placental gene expression is scarce. We have completed the first whole-genome profiling of human placental gene expression dynamics (GeneChips, Affymetrix) from early to mid- gestation (10 samples; gestational weeks 5 to 18) and report 154 genes with considerable change in transcript levels (FDR P<0.1). Functional enrichment analysis revealed >200 GO categories that are statistically over-represented among 105 genes with dynamically increasing transcript levels. Analysis in an extended sample (n=43; gestational weeks 5 to 41) conformed a highly significant (FDR P<0.05) expressional peak in mid-gestation placenta for ten genes: BMP5, CCNG2, CDH11, FST, GATM, GPR183, ITGBL1, PLAGL1, SLC16A10, STC1. A central hypothesis of our study states that the aberrant expression of genes characteristic to mid-gestation placenta may contribute to affected fetal growth, maternal preeclampsia (PE) or gestational diabetes (GD). The gene STC1 coding for Stanniocalcin 1 (STC1) was identified with a sharp placental expressional peak in mid-gestation, increased mRNA levels at term and significantly elevated STC1 protein levels in post-partum maternal plasma in all pregnancy complications. The highest STC1 levels were identified in women, who developed simultaneously PE and delivered an SGA baby (median 731 vs 418 pg/ml in controls; P=0.001). CCNG2 and LYPD6 exhibited significantly increased placental mRNA expression and enhanced intensity of immunohistochemistry staining in placental sections all studied in GD and PE cases. Aberrant expression of mid-gestation specific genes in pregnancy complications at term indicates the importance of the fine-scale tuning of the temporal dynamics of transcription regulation in placenta. Observed significantly elevated plasma STC1 in complicated pregnancies warrants further investigations of its potential as a biomarker. Interestingly, a majority of genes with high expression in mid-gestation placenta have also been implicated in adult complex disease. This observation promotes a recently opened discussion on the role of placenta in developmental programming.
Mid-gestational gene expression profile in placenta and link to pregnancy complications.
Specimen part
View SamplesIntra-islet crosstalk between islet cells is critical in orchestrating the body’s response to changes in blood glucose levels, but is incompletely understood. In this study, we used transgenic mouse lines that allowed the purification and transcriptomic characterisation of alpha, beta, and delta cells, yielding an RNA-sequencing database that can be searched for regulatory proteins which are differentially expressed between cell types. As an illustrative example, we examined the expression of g-protein coupled receptors, and found that the ghrelin receptor, Ghsr, was highly expressed in delta cells compared to alpha and beta cells. GHSR excitation elicited increases in cytosolic calcium levels in primary delta cells. In the perfused pancreas, the application of ghrelin stimulated somatostatin secretion, correlating with a decrease in insulin and glucagon release, which was sensitive to somatostatin receptor antagonism. These results show that ghrelin acts specifically on delta cells within pancreatic islets to affect blood glucose regulation. Overall design: Examination of transcriptomic profiles obtained from pancreatic alpha, beta and delta cells
Transcriptomic profiling of pancreatic alpha, beta and delta cell populations identifies delta cells as a principal target for ghrelin in mouse islets.
Specimen part, Cell line, Subject
View SamplesInterferons have been ascribed to mediate antitumor effects. IRF-1 is a major target gene of interferons. It inhibits cell proliferation and oncogenic transformation. Here we show that 60% of all mRNAs deregulated by oncogenic transformation mediated by c-myc and H-ras are reverted to the expression levels of non-transformed cells by IRF-1. These include cell cycle regulating genes. Activation of IRF-1 decreases cyclin D1 expression and CDK4 kinase activity concomitant with dephosphorylation of pRb. These effects of IRF-1 are mediated by inhibition of the MEK-ERK pathway and a transcriptional repression of cyclin D1. IRF-1 mediated effects on cell cycle progression were found to be overridden by ectopic expression of cyclin D1. Ablation of cyclin D1 by RNA interference experiments prevents transformation and tumor growth in nude mice. The data demonstrate that cyclin D1 is a key target for IRF-1 mediated tumor suppressive effects.
Tumor suppression by IFN regulatory factor-1 is mediated by transcriptional down-regulation of cyclin D1.
Specimen part
View SamplesLarge-scale genomic studies have identified multiple somatic aberrations in breast cancer, including copy number alterations, translocations, and point mutations. Still, identifying causal variants and emergent vulnerabilities that arise as a consequence of genetic alterations remain major challenges. We performed whole genome shRNA “dropout screens” on 77 breast cancer cell lines. Using a new hierarchical linear regression algorithm to score our screen results and integrate them with accompanying detailed genetic and proteomic information, we identify novel vulnerabilities in breast cancer, including new candidate “drivers,” and reveal general functional genomic properties of cancer cells. Comparisons of gene essentiality with drug sensitivity data suggest potential resistance mechanisms, novel effects of existing anti-cancer drugs, and new opportunities for combination therapy. Finally, we demonstrate the utility of this large dataset by identifying BRD4 as a potential target in luminal breast cancer, and PIK3CA mutations as a resistance determinant for BET-inhibitors. Additional formatted data can be found at http://neellab.github.io/bfg/. Code and tutorials for the siMEM algorithm can be found at http://neellab.github.io/simem/. Overall design: RNA-Seq expression profiling of 82 breast cancer cell lines without replicates or control samples
Functional Genomic Landscape of Human Breast Cancer Drivers, Vulnerabilities, and Resistance.
No sample metadata fields
View SamplesEnteroendocrine L-cells release hormones that control metabolism and appetite and are targets under investigation for the treatment of diabetes and obesity. Understanding L-cell diversity and expression profiles is critical for identifying target receptors that will translate into altered hormone secretion. We performed single cell RNA sequencing of mouse L-cells from the upper small intestine to distinguish cellular populations, revealing that L-cells form 3 major clusters: a group with typical characteristics of classical L-cells, including high expression of Gcg and Pyy; a cell type overlapping with Gip-expressing K-cells; and a unique cluster expressing Tph1 and Pzp that was predominantly located in duodenal villi and co-produced 5HT. Expression of G-protein coupled receptors differed between clusters, suggesting the cell types are differentially regulated, and would be differentially targetable. Our findings support the emerging concept that many enteroendocrine cell populations are highly overlapping, with individual cells producing a range of peptides previously assigned to distinct cell types. Overall design: Single cell RNA sequencing of mouse duodenal L-cells cells
Single-cell RNA-sequencing reveals a distinct population of proglucagon-expressing cells specific to the mouse upper small intestine.
Specimen part, Subject
View SamplesEndogenous oligodendrocyte progenitor cells (OPCs) are a promising target to improve functional recovery after spinal cord injury (SCI) by remyelinating denuded, and therefore vulnerable, axons. Demyelination is the result of a primary insult and secondary injury, leading to conduction blocks and long-term degeneration of the axons, which subsequently can lead to the loss of their neuron. In response to SCI, dormant OPCs can be activated and subsequently start to proliferate and differentiate into mature myelinating oligodendrocytes (OLs). Therefore, researchers strive to control OPC responses, and utilize small molecule screening approaches in order to identify mechanisms of OPC activation, proliferation, migration and differentiation. Overall design: DEG analysis of primary OPC and OL populations, 5 biological replicates per population
Primary Spinal OPC Culture System from Adult Zebrafish to Study Oligodendrocyte Differentiation <i>In Vitro</i>.
No sample metadata fields
View SamplesComparison between cell lines from 9 different cancer tissue of origin types (Breast, Central Nervous System, Colon, Leukemia, Melanoma, Non-Small Cell Lung, Ovarian, Prostate, Renal) from NCI-60 panel
Multifactorial regulation of E-cadherin expression: an integrative study.
Sex, Age, Specimen part, Disease, Disease stage, Cell line, Time
View SamplesExpression data were generated on 136 subjects from the COPDGene study using Affymetrix microarrays. Multiple linear regression with adjustment for covariates (gender, age, body mass index, family history, smoking status, pack years) was used to identify candidate genes and Ingenuity Pathway Analysis was used to identify candidate pathways.
Peripheral blood mononuclear cell gene expression in chronic obstructive pulmonary disease.
Sex, Specimen part
View SamplesCultured organotypic cerebellar slices were exposed for different time points with either prions (RML) versus non-infectious brain homogenate (NBH) or ligands to the globular domain of the prion protein (POM1) vs IgG
Prion infections and anti-PrP antibodies trigger converging neurotoxic pathways.
Specimen part, Treatment
View SamplesEpithelial tumor cells (E) underwent EMT in vivo in FVB/N mice generating mesenchymal tumors. Mesenchymal cell lines (M1-M4) were each derived from a different mouse. This study compares gene expression between these two different tumor types.
Immune-induced epithelial to mesenchymal transition in vivo generates breast cancer stem cells.
No sample metadata fields
View Samples