The endocytic receptor megalin constitutes the main pathway for clearance of plasma proteins from the glomerular filtrate in the proximal tubules. However, little is know about the mechanisms that control receptor activity. A widely discussed hypothesis states that the intracellular domain (ICD) of megalin, released upon ligand binding, acts as a transcription regulator to suppress receptor expression - a mechanism proposed to safeguard the proximal tubules from protein overload. Here, we have put this hypothesis to the test by generating a mouse model co-expressing the soluble ICD and the full-length receptor. Despite pronounced expression in the proximal tubules, the ICD failed to exert any effects on renal proximal tubular function such as megalin expression, protein retrieval, or renal gene transcription. Thus, our data argue that the ICD does not play a role in regulation of megalin activity in vivo in the proximal tubules.
The soluble intracellular domain of megalin does not affect renal proximal tubular function in vivo.
Sex, Age, Specimen part
View SamplesWhole testes were dissected from adult males. RNA from five or six biological replicates were generated and the expression profiles were determined using Affymetrix Drosophila Genechip 1 arrays. Comparisons between the bgcn- and Os+bgcn- groups allowed for the identification of stem cell genes.
Novel regulators revealed by profiling Drosophila testis stem cells within their niche.
No sample metadata fields
View SamplesDifferentially expressed genes between 171 human soft tissue sarcomas with complex genomics
From PTEN loss of expression to RICTOR role in smooth muscle differentiation: complex involvement of the mTOR pathway in leiomyosarcomas and pleomorphic sarcomas.
Sex, Specimen part, Cell line
View SamplesPrimary liver tumours include hepatocellular carcinomas (HCC), cholangiocarcinomas (CC) and a group of rare tumours exhibiting biliary and hepatocytic differentiation called combined hepatocholangiocarcinomas (cHCC-CC). To better define this latter group, we take advantage of a series of these tumours based on their morphological characteristics and we performed transcriptional analysis allowing thereafter global comparison with published data. We show that most cHCC-CCs express progenitor cell traits, are committed to biliary lineage and are mainly associated to the activation of Wnt/beta-catenin and TGFbeta signalling pathways. Wnt/beta-catenin pathway activation in cHCC-CC is evidenced by the expression of both its direct targets such as LEF1 and EPCAM. In addition, extracellular matrix (ECM) genes and ECM-remodelling genes which are upon the control of TGF profibrotic program were found up-regulated in cHCC-CC. Interestingly, we show that CC and most cHCC-CC share characteristics associated to a subtype of poorly differentiated HCC suggesting that these tumours could originate from a stem/progenitor cell. The plasticity of these cells may explain the phenotypical heterogeneity of these tumors with the maintenance of some hepatocellular differentiation features such as albumin expression. Interestingly, this is shared by at least one third of CC, raising the hypothesis of a potential continuum between CC, cHCC-CC and poorly differentiated HCC.
Combined hepatocellular-cholangiocarcinomas exhibit progenitor features and activation of Wnt and TGFβ signaling pathways.
Sex, Specimen part
View Samplesß1-integrin is the major ß-integrin subunit expressed in both lens epithelial and fiber cells. Our previous research indicated that ß1-integrin is essential for the maintenance of lens epithelial integrity and survival in late embryonic lens development (Simirskii et al, 2009). Lack of ß1-integrin in the lens will lead to severe micropthalmia and lack of lens in adult mice. In order to study the mechanisms involved, high throughput RNA sequencing (RNAseq) was performed to determine the genes that are differentially expressed between E15.5 wild type (WT) lenses and lenses that lack ß1-integrin expression due to the action of MLR10 CRE (ß1-cKO). The methodology used here is similar to the other RNAseq experiments that were previously performed in our lab (Manthey et al., 2014a and Audette et al, 2015) (Geo accession: GSE 49949 and GSE69940) . Meanwhile, the filtering criteria and processing procedures were also published (Manthey et al., 2014b). Compared to WT, 120 genes were found to be differentially expressed in ß1-cKO lenses. Moreover, bioinformatics tools (DAVID (the database for Annotation, Visulization and Integrated Discovery), and PANTHER (Protein Analysis through Evolutionary Relationship) classification system) as well as manual literature searching was applied for further data analysis. It showed that genes involved in EMT and stress-responses were differentially expressed in ß1-cKO compared to that of WT. Description of filtering criteria: To identify the differentially expressed genes, pair-wise qCML method exact tests with a Benjamini Hochberg false discovery rate correction greater than the threshold of P<0.05 was applied, which identified 5120 genes. As previously described (Manthey et al., 2014b), most of the genes differentially expressed between inbred C57Bl/6 <har> and mice with a mixed background were below a threshold of 2.5 fold change. Therefore, all differentially expressed genes with a less than 2.5 fold change were filtered out. Further, genes whose expression level were not high enough to be biologically significant were also filtered out, based on the RPMK (Reads per Kilobase per million reads) value. Any gene in the final list has RPKM greater that 2 in either WT or ß1-cKO samples, a value that corresponds to approximately 1 mRNA molecule per cell. By applying a combination of these filtering criteria, 120 differentially expressed genes were found, which could potentially elucidate the molecular connections between conditional deletion of ß1-intergrin from the lens and the observed phenotypic abnormalities. Manthey, A. L., Lachke, S. A., FitzGerald, P. G., Mason, R. W., Scheiblin, D. A., McDonald, J. H. and Duncan, M. K. (2014a) ''Loss of Sip1 leads to migration defects and retention of ectodermal markers during lens development'', Mech Dev 131: 86-110. Manthey, A. L., Terrell, A. M., Lachke, S. A., Polson, S. W. and Duncan, M. K. (2014b) ''Development of novel filtering criteria to analyze RNA-sequencing data obtained from the murine ocular lens during embryogenesis'', Genom Data 2: 369-374. Overall design: RNA-Seq comparison of C57Bl/6 <har> wild type controls and ß1-integrin conditional knockout lenses at E15.5, three biological replicates were used in each group
β1-Integrin Deletion From the Lens Activates Cellular Stress Responses Leading to Apoptosis and Fibrosis.
Specimen part, Subject
View SamplesThe Runx genes are important in development and cancer, where they can act either as oncogenes or tumour supressors. We compared the effects of ectopic Runx expression in established fibroblasts, where all three genes produce an indistinguishable phenotype entailing epithelioid morphology and increased cell survival under stress conditions. Gene array analysis revealed a strongly overlapping transcriptional signature, with no examples of opposing regulation of the same target gene. A common set of 50 highly regulated genes was identified after further filtering on regulation by inducible RUNX1-ER. This set revealed a strong bias toward genes with annotated roles in cancer and development, and a preponderance of targets encoding extracellular or surface proteins reflecting the marked effects of Runx on cell adhesion.
Gene array analysis reveals a common Runx transcriptional programme controlling cell adhesion and survival.
No sample metadata fields
View SamplesWe analyzed the generation of mouse gliomas following the overexpression of PDGF-B in embryonic neural progenitors. Comparison of our microarray data, with published gene expression data sets for many different murine neural cell types, revealed a closest relationship between our tumor cells and oligodendrocyte progenitor cells, confirming definitively that PDGF-B-induced gliomas are pure oligodendrogliomas.
PDGF-B induces a homogeneous class of oligodendrogliomas from embryonic neural progenitors.
No sample metadata fields
View SamplesThis SuperSeries is composed of the SubSeries listed below.
RNA sequencing validation of the Complexity INdex in SARComas prognostic signature.
Time
View SamplesWe validated the technological and material transfers of the CINSARC signature.
RNA sequencing validation of the Complexity INdex in SARComas prognostic signature.
Time
View SamplesOne of the main problems in managing desmoids tumors is their locoregional aggressiveness and their high ability to recur after initial treatment. In our work, with the goal to identify molecular markers that can predict Progression-Free Survival, gene-expression screening was conducted on 128 available independent untreated primary desmoid tumors using cDNA microarray. By analyzing expression profiles, we have identified, for the first time, a gene expression signature that is able to predict Progression-Free Survival. This molecular signature identified two groups with clearly distinct Progression-Free Survival in the two sets of subjects. Patients in good prognostic group had achieved a progression-free 2-year survival rate of 86% while patients in poor prognostic group had a progression-free 2-year survival rate of 44%.
Gene Expression Profiling of Desmoid Tumors by cDNA Microarrays and Correlation with Progression-Free Survival.
Sex, Age, Specimen part
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