Kaposis sarcoma (KS) is the most frequently occurring malignant tumor in patients infected with the human immunodeficiency virus. Recent studies have revealed that infection of vascular endothelial cells with Kaposi's sarcoma-associated herpes virus in vitro results in a lymphatic re-programming of these cells, with potent induction of the lymphatic marker genes podoplanin and VEGFR-3 which is mediated by upregulation of the transcription factor Prox1. However, the potential effects of Prox1 expression on the biology of KS and, in particular, on the aggressive and invasive behavior of KS tumors in vivo have remained unknown. We stably expressed Prox1 cDNA in the two mouse hemangioendothelioma cell lines EOMA and Py-4-1, well-established murine models for kaposiform hemangioendothelioma. Surprisingly, we found that expression of Prox1 was sufficient to induce a more aggressive behavior of tumors growing in syngenic mice, leading to enhanced local invasion into the muscular layer and to cellular anaplasia. This enhanced malignant phenotype was associated with upregulation of several genes involved in proteolysis, cytoskeletal reorganisation and migration. Together, these results indicate that Prox1 plays an important, previously unanticipated role in mediating the aggressive behavior of vascular neoplasms such as Kaposi's sarcoma.
Prox-1 promotes invasion of kaposiform hemangioendotheliomas.
No sample metadata fields
View SamplesCellular mechanisms that contribute to low estradiol concentrations produced by the preovulatory ovarian follicle in cattle with a compromised metabolic status (such as lactatino) are largely unknown. To gain insight into the main metabolic mechanisms affecting preovulatory follicle function RNAseq profiling was conducted on non-lactating Holstein-Friesian heifers (n=16) and lactating Holstein-Friesian cows (n=17) at three stages of preovulatory follicle development: A) newly selected dominant follicle in the luteal phase (Selection); B) follicular phase before the LH surge (Differentiation) and C) pre-ovulatory phase after the LH surge (Luteinization). Based on a combination of RNA sequencing, ingenuity pathway analysis and Q-RT-PCR validation several important molecular markers involved in steroid biosynthesis, such as the expression of steroidogenic acute regulatory protein (STAR) within developing dominant follicles, were identified to be affected (downregulated) by the catabolic state. We propose that the adverse metabolic environment caused by lactation decreases preovulatory follicle function by affecting cholesterol transport into the mitochondria to initiate steroidogenesis. Overall design: Granulosa and Theca samples from the dominant follicle were taken from cows and heifers at stages: selection, differentiation and luteinization.
Effect of the metabolic environment at key stages of follicle development in cattle: focus on steroid biosynthesis.
Specimen part, Subject
View SamplesRNA expression was measured using RNA-seq Overall design: RNA levels in Mock-treated control Drosophila cells were compared to RNA levels in cells RNAi depleted for Ph, Sce, and Pc
Polycomb repressive complex 1 modifies transcription of active genes.
Subject
View SamplesRNA nascent transcription was measured using NT-seq Overall design: RNA nascent transcript levels in Mock-treated control Drosophila cells were compared to those in cells RNAi depleted for Ph and Sce
Polycomb repressive complex 1 modifies transcription of active genes.
Subject
View SamplesWe report that developmental competition between sympathetic neurons for survival is critically dependent on a sensitization process initiated by target innervation and mediated by a series of feedback loops. Target-derived nerve growth factor (NGF) promoted expression of its receptor TrkA in neurons and prolonged TrkA-mediated signals. NGF also controlled expression of brain derived neurotrophic factor (BDNF) and neurotrophin-4 (NT4), which, through the receptor p75, can kill neighboring neurons with low retrograde NGFTrkA signaling whereas neurons with high NGFTrkA signaling are protected. Perturbation of any of these feedback loops disrupts the dynamics of competition. We suggest that three target-initiated events are essential for rapid and robust competition between neurons: sensitization, paracrine apoptotic signaling, and protection from such effects.
A model for neuronal competition during development.
No sample metadata fields
View SamplesThe goal of the current study was to identify changes in gene expression in the stomach muscularis that may be contributing to altered gastric motility in gastroparesis and obesity. Overall design: Stomach muscularis biopsies were obtained from human subjects with low BMI and normal gastric motility (low BMI control, n=6), subjects with high BMI but normal gastric motility (high BMI control, n=6), subjects with low BMI and gastroparesis (low BMI gastroparesis, n=6) and from subjects with high BMI and gastroparesis (High BMI gastroparesis, n=4). RNA was isolated and subjected to whole transcriptome sequencing.
Transcriptome profiling reveals significant changes in the gastric muscularis externa with obesity that partially overlap those that occur with idiopathic gastroparesis.
Specimen part, Subject
View SamplesWe tested the hypothesis that increasing matrix stiffness on which normal human lung fibroblasts are grown promotes the expression of a fibrogenic cellular transcriptomic program.
Feedback amplification of fibrosis through matrix stiffening and COX-2 suppression.
Sex, Specimen part, Race
View SamplesAccording to Dobzhansky-Muller model, hybrid sterility is a consequence of independent evolution of related taxa resulting in incompatible interaction during gametogenesis of their hybrids. We proposed that asynapsis of heterospecific chromosomes in meiotic prophase provides a general and recurrently evolving trigger for the meiotic arrest of interspecific F1 hybrids. We used genome-wide expression profiling to quantify misexpression of Chr X and Chr Y genes.
Mechanistic basis of infertility of mouse intersubspecific hybrids.
Age, Specimen part
View SamplesReliable clinical tests for predicting cancer chemotherapy response are not available and individual markers failed to correctly predict resistance against anticancer agents. We hypothesized that gene expression patterns attributable to chemotherapy-resistant cells can be used as a classification tool for chemoresistance and provide novel candidate genes involved in anthracycline resistance mechanisms. We contrasted the expression profiles of 4 different human tumor cell lines of gastric, pancreatic, colon and breast origin and of their counterparts resistant to the topoisomerase inhibitors daunorubicin or doxorubicin. We also profiled the sensitive parental cells treated with doxorubicin for 24h. We interrogated Affymetrix HGU133A and U95A arrays independently. We applied two independent methods for data normalization and used Prediction Analysis of Microarrays (PAM) for feature selection. In addition, we established data sets related to drug resistance by using a virtual array composed of features represented on both types of oligonucleotide arrays. We identified 71 candidate genes associated with doxorubicine/daunorubicine resistance. To validate the microarray data, we also analyzed the expression of 12 selected genes by quantitative RT-PCR or immunocytochemistry, respectively. While the comparison of drug-sensitive versus drug-resistant cells yields candidates associated with drug resistance, the 24h treatment of sensitive parental cells produced a distinct transcriptional profile related to short-term drug effects.
PSMB7 is associated with anthracycline resistance and is a prognostic biomarker in breast cancer.
No sample metadata fields
View SamplesReliable clinical tests for predicting cancer chemotherapy response are not available and individual markers failed to correctly predict resistance against anticancer agents. We hypothesized that gene expression patterns attributable to chemotherapy-resistant cells can be used as a classification tool for chemoresistance and provide novel candidate genes involved in anthracycline resistance mechanisms. We contrasted the expression profiles of 4 different human tumor cell lines of gastric, pancreatic, colon and breast origin and of their counterparts resistant to the topoisomerase inhibitors daunorubicin or doxorubicin. We also profiled the sensitive parental cells treated with doxorubicin for 24h. We interrogated Affymetrix HGU133A and U95A arrays independently. We applied two independent methods for data normalization and used Prediction Analysis of Microarrays (PAM) for feature selection. In addition, we established data sets related to drug resistance by using a virtual array composed of features represented on both types of oligonucleotide arrays. We identified 71 candidate genes associated with doxorubicine/daunorubicine resistance. To validate the microarray data, we also analyzed the expression of 12 selected genes by quantitative RT-PCR or immunocytochemistry, respectively. While the comparison of drug-sensitive versus drug-resistant cells yields candidates associated with drug resistance, the 24h treatment of sensitive parental cells produced a distinct transcriptional profile related to short-term drug effects.
PSMB7 is associated with anthracycline resistance and is a prognostic biomarker in breast cancer.
No sample metadata fields
View Samples