Nonsense-mediated RNA decay (NMD) is a highly conserved pathway that selectively degrades specific subsets of RNA transcripts. Here, we provide evidence that NMD regulates early human developmental cell fate. We found that NMD factors tend to be expressed at higher levels in human pluripotent cells than differentiated cells, raising the possibility that NMD must be downregulated to permit differentiation. Loss- and gain-of-function experiments in human embryonic stem cells (hESCs) demonstrated that, indeed, NMD downregulation is essential for efficient generation of definitive endoderm. RNA-seq analysis identified NMD target transcripts induced when NMD is suppressed in hESCs, including many encoding signaling components. This led us to test the role of TGF-b and BMP signaling, which we found NMD acts through to influence definitive endoderm vs. mesoderm fate. Our results suggest that selective RNA decay is critical for specifying the developmental fate of specific human embryonic cell lineages. Overall design: Examination of differential gene expression in hESCs upon loss of UPF1.
Nonsense-Mediated RNA Decay Influences Human Embryonic Stem Cell Fate.
Specimen part, Cell line, Subject
View SamplesWe assessed the effect of RNAi-mediated MAP kinase cascade signaling blockade in primary human keratinocytes. Two sets of siRNA targeting different regions of the Erk1/2 genes were used, enabling identification of off-target siRNA effects.
Erk1/2 MAP kinases are required for epidermal G2/M progression.
Specimen part
View SamplesExpression analysis of 36 pancreatic ductal adenocarcinoma tumors and matching normal pancreatic tissue samples from pancreatic cancer patients of the Clinical Institute Fundeni (ICF) using Affymetrix U133 Plus 2.0 whole-genome chips.
Combined gene expression analysis of whole-tissue and microdissected pancreatic ductal adenocarcinoma identifies genes specifically overexpressed in tumor epithelia.
Subject
View SamplesCharacterization of preclinical models of intrahepatic cholangiocarcinoma progression that reliably recapitulate altered molecular features of the human disease. Here, we performed comprehensive gene expression profiling of cholangiocarcinoma tumors arising from bile duct inoculation of different grade malignant rat cholangiocytes.
Differential gene expression profiling of cultured neu-transformed versus spontaneously-transformed rat cholangiocytes and of corresponding cholangiocarcinomas.
Sex
View SamplesLow-oxygen tolerance is supported by an adaptive response that includes a coordinate shift in metabolism and the activation of a transcriptional program that is driven by the hypoxia-inducible factor (HIF) pathway. The precise contribution of HIF-1 in the adaptive response, however, has not been determined. Here we investigate how HIF-1 influences hypoxic adaptation throughout Drosophila development. We find that hypoxic-induced transcriptional changes are comprised of HIF-dependent and HIF-independent pathways that are distinct and separable. We show that normoxic set-points of carbohydrate metabolites are significantly altered in dHIF mutants and that these animals are unable to mobilize glycogen in hypoxia. Furthermore, we find that the estrogen-related receptor (dERR), which is a global regulator of aerobic glycolysis in larvae, is required for a competent hypoxic response. dERR binds to dHIF and participates in the HIF-dependent transcriptional program in hypoxia. In addition, dERR acts in the absence of dHIF in hypoxia and a significant portion of HIF-independent transcriptional responses can be attributed to dERR actions, including upregulation of glycolytic transcripts. These results indicate that competent hypoxic responses arise from complex interactions between HIF-dependent and -independent mechanisms, and that dERR plays a central role in both of these programs.
HIF- and non-HIF-regulated hypoxic responses require the estrogen-related receptor in Drosophila melanogaster.
Specimen part
View SamplesThe increased -smooth muscle-actin positive cancer-associated fibroblastic cells (CAF) in the desmoplastic stroma may relate to a more aggressive cancer and worse survival outcomes for intrahepatic cholangiocarcinoma (ICC) patients
Novel organotypic culture model of cholangiocarcinoma progression.
Specimen part, Disease
View SamplesPolycystic ovary syndrome (PCOS), the most common cause of anovulatory infertility, is characterized by increased ovarian androgen production, arrested follicle development, and is frequently associated with insulin resistance. These PCOS phenotypes are associated with exaggerated ovarian responsiveness to FSH and increased pregnancy loss. To examine whether the perturbations in follicle growth and the intrafollicular environment affects development of the mature PCOS oocyte, genes that are differentially expressed in PCOS compared to normal oocytes were defined using microarray analysis. This analysis detected approximately 8000 transcripts. Hierarchical clustering and principal component analysis revealed differences in global gene expression profiles between normal and PCOS oocytes. 374 genes had a statistically-significant increase or decrease in mRNA abundance in PCOS oocytes. A subset of these genes was associated with chromosome alignment and segregation during mitosis and/or meiosis, suggesting that increased mRNAs for these proteins may negatively affect oocyte maturation and/or early embryonic development. Of the 374 differentially expressed genes, 68 contained putative androgen receptor, retinoic acid receptor, and/or peroxisome proliferating receptor gamma binding sites, including 9 of the genes involved in chromosome alignment and segregation. These analyses demonstrated that normal and PCOS oocytes that are morphologically indistinguishable and of high quality exhibit different gene expression profiles. Furthermore, altered mRNA levels in the PCOS oocyte may contribute to defects in meiosis and/or mitosis which might impair oocyte competence for early development and therefore contribute to poor pregnancy outcome in PCOS.
Molecular abnormalities in oocytes from women with polycystic ovary syndrome revealed by microarray analysis.
No sample metadata fields
View SamplesPrimitive erythropoiesis in the mouse yolk sac is followed by definitive erythropoiesis resulting in adult erythrocytes. In comparison to definitive erythropoiesis little is known about the genes that control the embryonic erythroid program. The purpose of this study was to generate a profile of mouse embryonic yolk sac erythroid cells and identify novel regulatory genes differentially expressed in erythroid compared to non-erythroid (epithelial cells).
Identification of erythroid-enriched gene expression in the mouse embryonic yolk sac using microdissected cells.
No sample metadata fields
View SamplesCancer-related fatigue is one of the most frequent complaints among breast cancer survivors, with a major negative impact on general life. However, the etiology behind this syndrome is still unraveled. Gene expression analysis was performed on whole blood samples from breast cancer survivors classified as either fatigued or non-fatigued at two consecutive time points. The analysis identified several gene sets concerning plasma and B cell pathways as different between the fatigue and non-fatigue groups, suggesting that a deregulation in these pathways might underlie the fatigue syndrome. The fatigue group also showed a higher mean level of leucocytes, lymphocytes and neutrophiles compared with the non-fatigue group, thus further implicating the immune system in the biology behind the fatigue syndrome.
Alterations of gene expression in blood cells associated with chronic fatigue in breast cancer survivors.
Specimen part, Subject
View SamplesValidation of preclinical models of intrahepatic cholangiocarcinoma progression that reliably recapitulate altered molecular features of the human disease would provide an important resource for suggesting and testing of novel target-based therapies against this devastating cancer. In this study, comprehensive gene expression profiling in a novel orthotopic rat model of intrahepatic cholangiocarcinoma progression was carried out in an effort to identify potential therapeutic targets relevant to the progressive human cancer.
Intrahepatic cholangiocarcinoma progression: prognostic factors and basic mechanisms.
Sex, Specimen part
View Samples