Microarrays were used to analyse gene expression underlying early tumourigenesis in Eker rats. Distinct classes of up- and downregulated genes were identified in different preneoplasic lesion vs. microdissected normal (healthy) renal tubules.
Molecular characterization of preneoplastic lesions provides insight on the development of renal tumors.
Sex, Specimen part
View SamplesBy comparing to common tumor cells, genes were differencially expressed in pseudopalisading cells in human glioblastoma
Histology-based expression profiling yields novel prognostic markers in human glioblastoma.
No sample metadata fields
View SamplesThis work was designed to determine the role of the vascular endothelial growth factor A (VEGF) isoforms during early neuroepithelial development in the mammalian central nervous system (CNS), specifically in the forebrain. An emerging model of interdependence between neural and vascular systems includes VEGF, with its dual roles as a potent angiogenesis factor and neural regulator. Although a number of studies have implicated VEGF in CNS development, little is known about the role that the different VEGF isoforms play in early neurogenesis. We used a mouse model of disrupted VEGF isoform expression that eliminates the predominant brain isoform, VEGF164, and expresses only the diffusible form, VEGF120. We tested the hypothesis that VEGF164 plays a key role in controlling neural precursor populations in developing cortex. We used microarray analysis to compare gene expression differences between wild type and VEGF120 mice at E9.5, the primitive stem cell stage of the neuroepithelium. We quantified changes in PHH3-positive nuclei, neural stem cell markers (Pax6 and nestin) and the Tbr2-positive intermediate progenitors at E11.5 when the neural precursor population is expanding rapidly. Absence of VEGF164 (and VEGF188) leads to reduced proliferation without an apparent effect on the number of Tbr2-positive cells. There is a corresponding reduction in the number of mitotic spindles that are oriented parallel to the ventricular surface relative to those with a vertical or oblique angle. These results support a role for the VEGF isoforms in supporting the neural precursor population of the early neuroepithelium.
Vascular endothelial growth factor (VEGF) isoform regulation of early forebrain development.
Specimen part
View SamplesWe performed gene expression profilings of platelet-derived growth factor subunit B (PDGFB)-induced mouse glioma to compare the differential transcriptome profiles between Ctrl-T tumor cells and Olig2cKO tumor cells. Overall design: Expression profiling of Ctrl-T and Olig2cKO brain tumor (glioma) cells, normal oligodendrocyte progenitor cells (OPCs), normal astrocytes, and normal brain cortex by high-throughput sequencing.
Olig2-Dependent Reciprocal Shift in PDGF and EGF Receptor Signaling Regulates Tumor Phenotype and Mitotic Growth in Malignant Glioma.
Specimen part, Subject
View SamplesWe performed gene expression pofiling of of Olig2cKO and control glioma tumor and identified significantly changed genes Overall design: RNA-seq of control tumor tissues and Olig2cKO tumor tissues
Olig2-Dependent Reciprocal Shift in PDGF and EGF Receptor Signaling Regulates Tumor Phenotype and Mitotic Growth in Malignant Glioma.
No sample metadata fields
View SamplesNeurofibromatosis type II (NF2) is a disease that needs new solutions. Vestibular schwannoma (VS) growth cause progressive hearing loss, and the standard treatment including surgery and radiotherapy, can further damage the nerve. There is an urgent need to identify an adjunct therapy that, by enhancing the efficacy of radiation, can help lower the radiation dose and preserve hearing. The mechanisms underlying deafness in NF2 are still unclear. One of the major limitations in studying tumor-induced hearing loss is the lack of mouse models that allows hearing test. Here we developed a cerebellopontine angle (CPA) schwannomas model that faithfully recapitulates the tumor-induced hearing loss. Using this model we discovered that cMET blockade by crizotinib (CRZ) enhanced schwannoma radiosensitivity by enhancing DNA damage, and CRZ treatment combined with low-dose radiation was as effective as high-dose radiation. CRZ treatment had no adverse effect on hearing; however, it did not affect tumor-induced hearing loss, presumably because cMET blockade did not change tumor HGF levels. cMET gene knockdown study independently confirmed the role of cMET pathway in mediating the effect of CRZ. Furthermore, we evaluated the translational potential of cMET blockade in human schwannomas. We found that human NF2-associated and sporadic VSs showed significantly elevated HGF expression and cMET activation compared to normal nerves, which correlated with tumor growth and cyst formation. Using organoid brain slice culture, cMET blockade inhibited the growth of patient-derived schwannomas. Our findings provide the rationale and necessary data for the clinical translation of combined cMET blockade with radiation therapy in NF2 patients.
Targeting the cMET pathway augments radiation response without adverse effect on hearing in NF2 schwannoma models.
Sex, Age, Specimen part, Disease, Disease stage
View SamplesUnderstanding biological pathways critical for common neurofibromatosis type 1 (NF1) peripheral nerve tumors is essential, as tumor biomarkers, prognostic factors and therapeutics are all lacking. We used gene expression profiling to define transcriptional changes between primary normal Schwann cells (n = 10), NF1-derived primary benign neurofibroma Schwann cells (n = 22), malignant peripheral nerve sheath tumor (MPNST) cell lines (n = 13), benign neurofibromas (n = 26) and MPNST (n = 6). Dermal and plexiform neurofibromas were indistinguishable. A prominent theme in the analysis was aberrant differentiation. Neurofibromas repressed gene programs normally active in Schwann cell precursors and immature Schwann cells. MPNST signatures strongly differed; genes upregulated in the sarcomas were significantly enriched for genes activated in neural crest cells. We validated differential expression of 82 genes including the neural crest transcription factor SOX9 and SOX9 predicted targets. SOX9 immunoreactivity was robust in neurofibroma and MPSNT tissue sections and targeting SOX9 - strongly expressed in NF1-related tumors - caused MPNST cell death. SOX9 is a biomarker of neurofibroma and MPNST, and possibly a therapeutic target in NF1.
Integrative genomic analyses of neurofibromatosis tumours identify SOX9 as a biomarker and survival gene.
No sample metadata fields
View SamplesWe generated a gene replacement allele of the E-cadherin locus that express an N-cadherin-GFP fusion in ES cells. Expression profiles of homozygous and heterozygous knock-in ES cells were analyzed in comparison to wt ES cells.
Adhesion, but not a specific cadherin code, is indispensable for ES cell and induced pluripotency.
No sample metadata fields
View SamplesWe report the differential gene expression differences between control and Ovol2-deficent newborn keratinocytes Overall design: Two control and two Ovol2-deficent samples were isolated
An Ovol2-Zeb1 transcriptional circuit regulates epithelial directional migration and proliferation.
Specimen part, Subject
View SamplesTranscription factors drive organogenesis, from the initiation of cell fate decisions to the maintenance and implementation of these decisions. The Drosophila embryonic salivary gland provides an excellent platform for unraveling the underlying transcriptional networks of organ development because Drosophila is relatively unencumbered by significant genetic redundancy. The highly conserved FoxA family transcription factors are essential for various aspects of organogenesis in all animals that have been studied. Here, we explore the role of the single Drosophila FoxA protein Fork head (Fkh) in salivary gland organogenesis using two genome-wide strategies. A large-scale in situ hybridization analysis reveals a major role for Fkh in maintaining the salivary gland fate decision and controlling salivary gland physiological activity, in addition to its previously known roles in morphogenesis and survival. The majority of salivary gland genes (59%) are affected by fkh loss, mainly at later stages of salivary gland development. We show that global expression of Fkh cannot drive ectopic salivary gland formation. Thus, unlike the worm FoxA protein PHA-4, Fkh does not function to specify cell fate. In addition, Fkh only indirectly regulates many salivary gland genes, which is also distinct from the role of PHA-4 in organogenesis. Our microarray analyses reveal unexpected roles for Fkh in blocking terminal differentiation and in endoreduplication in the salivary gland and in other Fkh-expressing embryonic tissues. Overall, this study demonstrates an important role for Fkh in determining how an organ preserves its identity throughout development and provides an alternative paradigm for how FoxA proteins function in organogenesis.
Genome-wide analysis reveals a major role in cell fate maintenance and an unexpected role in endoreduplication for the Drosophila FoxA gene Fork head.
No sample metadata fields
View Samples