Rat kidney in normo- and hypotensive animals.
A physiogenomic approach to study the regulation of blood pressure.
No sample metadata fields
View SamplesBackground & Aims: Ursodeoxycholic acid (UDCA) attenuates chemical and colitis-induced colon carcinogenesis in animal models. We investigated its mechanism of action on normal intestinal cells, in which carcinogenesis- or inflammation-related alterations do not interfere with the result. Methods: Alterations of gene expression were identified in Affymetrix arrays in isolated colon epithelium of mice fed with a diet containing 0.4% UDCA and were confirmed in the normal rat intestinal cell line IEC-6 by RT-PCR. The effect of the insulin receptor substrate 1 (Irs-1) expression and of ERK phosphorylation on proliferation was investigated in vitro by flow cytometry, western blotting, siRNA-mediated gene suppression or by pharmacological inhibition of the kinase activity. The ERK1-effect on Irs-1 transcription was tested in a reporter system. Results: UDCA-treatment in vivo suppressed potential pro-proliferatory genes including Irs-1 and reduced cell proliferation by more than 30%. In vitro it neutralised the proliferatory signals of IGF-1 and EGF and slowed down the cell cycle. Irs-1 transcription was suppressed due to high ERK1 activation. Both Irs-1 suppression and the persistent high ERK activation inhibited proliferation. Conversely, the decrease of phosphorylation of ERK1 (but not ERK2) or of its expression partially abrogated the inhibitory effects of UDCA. Conclusions: UDCA inhibits proliferation of intestinal epithelial cells by acting upon IGF-1 and EGF pathways and targeting ERK1 and, consequently, Irs-1. The inhibition of these pathways adds a new dimension to the physiological and therapeutic action of UDCA and, since both pathways are activated in inflammation and cancer, suggests new applications of UDCA in chemoprevention and chemotherapy.
UDCA slows down intestinal cell proliferation by inducing high and sustained ERK phosphorylation.
Specimen part, Cell line
View SamplesThe distinction between the Burkitt lymphoma and diffuse large B-cell lymphoma is imprecise using current diagnostic criteria. We applied transcriptional and genomic profiling to molecularly define Burkitt lymphoma. Gene expression profiling employing Affymetrix GeneChips (U133A) was performed in 220 mature aggressive B-cell lymphomas, including a core group of eight Burkitt lymphomas, which fulfilled all diagnostic criteria of the WHO classification. A molecular signature of Burkitt lymphoma was generated. Chromosomal abnormalities were detected by interphase fluorescence in-situ hybridization and array comparative genomic hybridization. The molecular Burkitt lymphoma signature identified 44 cases. Fifteen of these cases lacked a morphology typical for Burkitt/Burkitt-like lymphoma. The vast majority (88%) of the 176 lymphomas without the molecular Burkitt lymphoma signature represented diffuse large B-cell lymphomas. In 20% of these cases a MYC break was detectable which was associated with complex chromosomal changes. Our molecular definition of Burkitt lymphoma sharpens and extends the spectrum of Burkitt lymphoma. In mature aggressive B-cell lymphomas without a Burkitt lymphoma signature, a chromosomal break in the MYC locus proved to be associated with adverse clinical outcome.
A biologic definition of Burkitt's lymphoma from transcriptional and genomic profiling.
Sex, Age
View SamplesThe hair of all mammals consists of terminally differentiated cells that undergo a specialized form of apoptosis called cornification. While DNA is destroyed during cornification, the extent to which RNA is lost is unknown. Here we find that multiple types of RNA are incompletely degraded after hair shaft formation in both mouse and human. Notably, mRNAs and short regulatory microRNAs (miRNAs) are stable in the hair as far as 10 cm from the scalp. To better characterize the post-apoptotic RNAs that escape degradation in the hair, we performed sequencing (RNA-seq) on RNA isolated from hair shafts pooled from several individuals. This hair shaft RNA library, which encompasses different hair types, genders, and populations, revealed 7,193 mRNAs, 449 miRNAs and thousands of unannotated transcripts that remain in the post-apoptotic hair. A comparison of the hair shaft RNA library to that of viable keratinocytes revealed surprisingly similar patterns of gene coverage and indicates that degradation of RNA is highly inefficient during apoptosis of hair lineages. The generation of a hair shaft RNA library could be used as months of accumulated transcriptional history useful for retrospective detection of disease, drug response and environmental exposure.
The post-apoptotic fate of RNAs identified through high-throughput sequencing of human hair.
No sample metadata fields
View SamplesIn order to investigate the genes that might be regulated by the activating signal cointegrator 1 (ASC-1) complex we performed an expression analysis using the GeneChip Human Gene 2.0 ST Array (Affymetrix)
Mutations in Subunits of the Activating Signal Cointegrator 1 Complex Are Associated with Prenatal Spinal Muscular Atrophy and Congenital Bone Fractures.
Specimen part
View SamplesERG overexpression was conducted in stably transfected K562 cell line with a tet-on inducible plasmid habouring ERG3. Prolonged induction of ERG (8 days) produced spindle cell shape changes whereas non-induced cells retained the round morphology. In oder to determine the genes responsible for inducing cell shape changes, a genome wide transcriptional screen was conducted.
ERG induces a mesenchymal-like state associated with chemoresistance in leukemia cells.
Cell line, Treatment
View SamplesComplete identification of the bone marrow niche remains one of the most progressing fields. Attempts to identify soluble factors involved in stem cell renewal have been less successful. We have previously shown that endothelial cells (EC) can induce the long-term proliferation of hematopoietic progenitor cells (HPC), especially when they had been subjected to an inflammatory stimulus like interleukins (IL) 1.
Interleukin 32 promotes hematopoietic progenitor expansion and attenuates bone marrow cytotoxicity.
Specimen part, Treatment, Time
View SamplesPreeclampsia complicates more than 3% of all pregnancies in the United States and Europe. High-risk populations include women with diabetes, dyslipidemia, thrombotic disorders, hyperhomocysteinemia, hypertension, renal diseases, previous preeclampsia, twin pregnancies, and low socioeconomic status. In the latter case, the incidence may increase to 20% to 25%. Preeclampsia is a major cause of maternal and fetal morbidity and mortality. Preeclampsia is defined by systolic blood pressure of more than 140 mm Hg and diastolic blood pressure of more than 90 mm Hg after 20 weeks gestation in a previously normotensive patient, and new-onset proteinuria. Abnormal placentation associated with shallow trophoblast invasion (fetal cells from outer cell layer of the blastocyst) into endometrium (decidua) and improper spiral artery remodeling in the decidua are initial pathological steps.
Dysregulation of the circulating and tissue-based renin-angiotensin system in preeclampsia.
No sample metadata fields
View SamplesThe aim of this study is to generate and validate biomarkers to stratify patients with Barretts esophagus in terms of risk for developing cancer. We studied gene expression profiling in 69 frozen specimens, consisting of esophageal squamous epithelium from 19 healthy subjects, 20 specimens from patients with Barretts esophagus and 21 cases of esophageal adenocarcinoma, 9 cased of esophageal squamous cell carcinoma by whole genome microarray analysis. Laser capture microdissection technique was applied to procure cells from defined regions of Barretts esophagus metaplasia and esophageal adenocarcinoma. Microarray results were validated by quantitative real-time polymerase chain reaction (qRT-PCR) in an independent cohort consisting of 42 cases. Furthermore, immunohistochemistry was performed using antibodies to two selected target molecules on a third independent cohort of 36 specimens, consisting of 36 cases. A total of 1176 genes were associated significantly with esophageal adenocarcinoma. The expression pattern of a 4 gene signature with the highest discriminant score based on linear discriminant analysis (GeneSpring GX10.2), was identified and validated by qRT-PCR in independent cohort.
Wdr66 is a novel marker for risk stratification and involved in epithelial-mesenchymal transition of esophageal squamous cell carcinoma.
Specimen part
View SamplesAcute myeloid leukemia (AML) is one of the most common and deadly forms of hematopoietic malignancies. We hypothesized that microarray studies could identify aberrantly expressed genes selectively expressed in AML blasts, believing that these genes may be potential therapeutic targets for adoptive T-cell strategies
No associated publication
Specimen part, Disease
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