Medulloblastoma is the most frequent malignant pediatric brain tumor. Considerable efforts are dedicated to identify markers that help to refine treatment strategies. The activation of the Wnt/beta-catenin pathway occurs in 10-15% of medulloblastomas and has been recently described as a marker for favorable patient outcome. We report a series of 72 pediatric medulloblastomas evaluated for beta-catenin immunostaining, CTNNB1 mutations, and studied by comparative genomic hybridization. Gene expression profiles were also available in a subset of 40 cases. Immunostaining of beta-catenin showed extensive nuclear staining (>50% of the tumor cells) in 6 cases and focal nuclear staining (<10% of cells) in 3 cases. The other cases exhibited either a signal strictly limited to the cytoplasm (58 cases) or were negative (5 cases). CTNNB1 mutations were detected in all beta-catenin extensively nucleopositive cases. The expression profiles of these cases documented a strong activation of the Wnt/beta-catenin pathway. Remarkably, 5 out of these 6 tumors showed a complete loss of chromosome 6. In contrast, cases with focal nuclear beta-catenin staining, as well as tumors with negative or cytoplasmic staining, never demonstrated CTNNB1 mutation, Wnt/beta-catenin pathway activation or chromosome 6 loss. Patients with extensive nuclear staining were significantly older at diagnosis and were in continuous complete remission after a mean follow-up of 75.7 months (range 27.5-121.2) from diagnosis. All three patients with a focal nuclear staining of beta-catenin died within 36 months from diagnosis. Altogether, these data confirm and extend previous observations that CTNNB1-mutated tumors represent a distinct molecular subgroup of medulloblastomas with favorable outcome, indicating that therapy de-escalation should be considered. Yet, international consensus on the definition criteria of this distinct medulloblastoma subgroup should be achieved.
Beta-catenin status in paediatric medulloblastomas: correlation of immunohistochemical expression with mutational status, genetic profiles, and clinical characteristics.
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View SamplesWine biological aging is a wine making process used to produce specific beverages in several countries in Europe, including Spain, Italy, France, and Hungary. This process involves the formation of a velum at the surface of the wine. Here, we present the first large scale comparison of all European flor strains involved in this process. We inferred the population structure of these European flor strains from their microsatellite genotype diversity and analyzed their ploidy. We show that almost all of these flor strains belong to the same cluster and are diploid, except for a few Spanish strains. Comparison of the array hybridization profile of six flor strains originating from these four countries, with that of three wine strains did not reveal any large segmental amplification. Nonetheless, some genes, including YKL221W/MCH2 and YKL222C, were amplified in the genome of four out of six flor strains. Finally, we correlated ICR1 ncRNA and FLO11 polymorphisms with flor yeast population structure, and associate the presence of wild type ICR1 and a long Flo11p with thin velum formation in a cluster of Jura strains. These results provide new insight into the diversity of flor yeast and show that combinations of different adaptive changes can lead to an increase of hydrophobicity and affect velum formation.
Population structure and comparative genome hybridization of European flor yeast reveal a unique group of Saccharomyces cerevisiae strains with few gene duplications in their genome.
No sample metadata fields
View SamplesWe used the microarrays to obtain the cancerous signatures of T-cell, B-cell, erythroid and megakaryoblastic leukemias in mice.
Gene profiling of the erythro- and megakaryoblastic leukaemias induced by the Graffi murine retrovirus.
No sample metadata fields
View SamplesConsumption of walnuts has slowed breast cancer growth and/or reduced the risk of breast cancer in mice. The significantly reduced mean tumor size or numbers of tumors was associated with changing the expressions of many genes that are associated with cancer growth, survival and metastasis. Many women treated for breast cancer are interested in reducing the risk for recurrence. The study was a non-placebo, two-arm, clinical trial. Women with lumps large enough for research and pathology biopsies were recruited to the trial. One or two additional biopsies were taken for gene expression analyses using next generation RNA Sequencing methods. The subjects randomized to the walnut group immediately began to consume 2 ounces of walnuts per day until follow-up surgery, if surgery were needed. At follow up surgery, additional biopsies were taken from the surgically removed, cancerous tissue for additional gene expression analyses. Changes in gene expression compared to baseline were determined in tumors of each individual woman in walnut-consuming and control groups. Overall design: Gene expression profiles of two samples from each of ten breast cancer patients were obtained via RNA-Seq in a 2x50bp paired-end design. The first sample was obtained from biopsy; the second sample was taken at the time of surgery 2-3 weeks later. Five patients consumed two one-ounce packets of walnuts daily between the biopsy and surgery, while the other five remained on their regular diet.
Dietary walnut altered gene expressions related to tumor growth, survival, and metastasis in breast cancer patients: a pilot clinical trial.
Specimen part, Subject
View SamplesCF's physiopathology is poorly explained by the mutation alone. The oxydative stress could be a major factor of this illness . Study its impact on transcriptome's CF cell line could be ameliorate our understanding of the evolution of cystic fibrosis.
Oxidative stress modulates the expression of genes involved in cell survival in ΔF508 cystic fibrosis airway epithelial cells.
Cell line, Treatment
View SamplesOur group originally developed clonal cell lines by limiting dilution of the parental cell line, and also stably transfected one of these cell lines with human phospholipase D2.
Differential Expression of Ccn4 and Other Genes Between Metastatic and Non-metastatic EL4 Mouse Lymphoma Cells.
Specimen part
View SamplesA key event in the pathogenic process of prion diseases is the conversion of the cellular prion protein (PrPC) to an abnormal and protease-resistant isoform (PrPSc). Mice lacking PrP are resistant to prion infection, and down-regulation of PrPC during prion infection prevents neuronal loss and the progression to clinical disease. These results are suggestive of the potential beneficial effect of silencing PrPC during prion diseases. However, the silencing of a protein that is widely expressed throughout the CNS could be detrimental to brain homeostasis. The physiological role of PrPC remains still unclear, but several putative functions have been proposed. Among these, several lines of evidence support PrPC function in neuronal development and maintenance.
Developmental influence of the cellular prion protein on the gene expression profile in mouse hippocampus.
Specimen part
View SamplesComparative analysis of Endodermal-like cell lines with demonstrated ability to support myocardial differentiation
A comparative analysis of extra-embryonic endoderm cell lines.
Specimen part
View SamplesAdult BALB/c female mice were injected intraperitoneally with a single dose at 20 mg per kg of antisense oligonucleotide either against miR-29a (5-TAACCGATTTCAGATGGTGCTA-3) or against a scrambled sequence (5-TCATTGGCATGTACCATGCAGCT-3 Antisense oligonucleotides contained 2-O-methoxyethyl (2-MOE), 2-flouro (2-F) 2'-alpha-flouro units with a phosphorothioate backbone (Regulus Therapeutics). Six days following the injection, liver was isolated, total RNA was prepared as described above, and the RNA was amplified and biotinylated using the MessageAmp Premier kit (Ambion). Samples (n=4 each experimental and control) were hybridized to Affymetrix GeneChip Mouse Genome 430 2.0 Arrays in the Childrens Hospital of Philadelphia Nucleic Acids Core Facilityand analyzed with the assistance of the Penn Bioinformatics Core. Probe intensities were normalized using the GCRMA method and the significance of the log2-transformed, GCRMA-normalized signal intensities was determined using SAM
MicroRNA profiling identifies miR-29 as a regulator of disease-associated pathways in experimental biliary atresia.
Sex, Specimen part, Treatment
View SamplesTo evaluate gene expression profiles on different dendritic cell subsets isolated from spleens of mice
CD28 Deficiency Enhances Type I IFN Production by Murine Plasmacytoid Dendritic Cells.
Sex
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