The expression profiles of 64 neuroblastic tumors (mainly neuroblastoma) were determined on Affymetrix chips HG U133 Plus 2.0.
Somatic and germline activating mutations of the ALK kinase receptor in neuroblastoma.
No sample metadata fields
View SamplesMedulloblastoma 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.
No sample metadata fields
View SamplesNeuroblastoma is an embryonal neoplasm that remains of dramatic prognosis in its aggressive forms. Activating mutations of the ALK tyrosine kinase receptor have been identified in sporadic and familial cases of this cancer. We generated knock-in mice carrying the two most frequent Alk mutations observed in neuroblastoma patients. We used microarrays to detail the global programme of gene expression underlying the impact of ALK mutations on neuroblastoma formation in a MYCN amplified background.
Activated Alk triggers prolonged neurogenesis and Ret upregulation providing a therapeutic target in ALK-mutated neuroblastoma.
Specimen part
View SamplesLong intergenic non-coding RNAs (lincRNAs) are emerging as integral components of signaling pathways in various cancer types. In neuroblastoma, only a handful of lincRNAs are known as upstream regulators or downstream effectors of oncogenes. Here, we exploit RNA sequencing data of primary neuroblastoma tumors, neuroblast precursor cells, neuroblastoma cell lines and various cellular perturbation model systems to define the neuroblastoma lincRNome and map lincRNAs up- and downstream of neuroblastoma driver genes MYCN, ALK and PHOX2B. Each of these driver genes controls the expression of a particular subset of lincRNAs, several of which are associated with poor survival and are differentially expressed in neuroblastoma tumors compared to neuroblasts. By integrating RNA sequencing data from both primary tumor tissue and cancer cell lines, we demonstrate that several of these lincRNAs are expressed in stromal cells. Deconvolution of primary tumor gene expression data revealed a strong association between stromal cell composition and driver gene status, resulting in differential expression of these lincRNAs. We also explored lincRNAs that putatively act upstream of neuroblastoma driver genes, either as presumed modulators of driver gene activity, or as modulators of effectors regulating driver gene expression. This analysis revealed strong associations between the neuroblastoma lincRNAs MIAT and MEG3 and MYCN and PHOX2B activity or expression. Together, our results provide a comprehensive catalogue of the neuroblastoma lincRNome, highlighting lincRNAs up- and downstream of key neuroblastoma driver genes. This catalogue forms a solid basis for further functional validation of candidate neuroblastoma lincRNAs. Overall design: CLB-GA was transduced with control or inducible shPHOX2B. The cells were treated with doxycycline for 5 days.
Integrative analysis identifies lincRNAs up- and downstream of neuroblastoma driver genes.
Cell line, Treatment, Subject
View SamplesRhabdoid Tumors (RT) are highly aggressive tumors that are frequently localized in the central nervous system (CNS) where they are termed atypical teratoid and rhabdoid tumors (ATRT). We generated conditional Smarcb1-deficient mouse model leads to CNS Smarcb1-deficient tumors.
The occurrence of intracranial rhabdoid tumours in mice depends on temporal control of Smarcb1 inactivation.
Specimen part
View SamplesBackground: Studies in mice have shown that PPAR is an important regulator of lipid metabolism in liver and a key transcription factor involved in the adaptive response to fasting. However, much less is known about the role of PPAR in human liver. Here we set out to study the function of PPAR in human liver via analysis of whole genome gene regulation in human liver slices treated with the PPAR agonist Wy14643.
The impact of PPARα activation on whole genome gene expression in human precision cut liver slices.
Sex, Specimen part, Treatment, Subject, Time
View SamplesLittle is known about the early transcriptional events in innate immune signaling in immature and tolerogenic monocyte-derived dendritic cells (DCs), the professional antigen-presenting cells of our immune system. TLR ligands usually induce a proinflammatory transcriptional response, whereas IL10 and/or dexamethasone induce a more tolerogenic phenotype.
MicroRNA genes preferentially expressed in dendritic cells contain sites for conserved transcription factor binding motifs in their promoters.
Specimen part
View SamplesGENES ASSOCIATED WITH THE CELL CYCLE, LINEAGE COMMITMENT AND IMMUNOMODULATORY POTENTIAL DISCRIMINATE HUMAN POSTNATAL STEM CELLS OF DIFFERENT ORIGIN.
Functional differences between mesenchymal stem cell populations are reflected by their transcriptome.
No sample metadata fields
View SamplesIn this study we aimed to identify a baseline intrahepatic transcriptional signature associated with response in chronic hepatitis B patients treated with peginterferon-alfa-2a (peg-IFN) and adefovir.
An intrahepatic transcriptional signature of enhanced immune activity predicts response to peginterferon in chronic hepatitis B.
Specimen part, Disease, Disease stage
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Drug-induced histone eviction from open chromatin contributes to the chemotherapeutic effects of doxorubicin.
Age, Specimen part, Cell line, Treatment, Time
View Samples