ABSTRACT: Comparing gene expression profiles of pigmented and amelanotic (MPNST-like) melanomas arising in the genetically engineered BRAF(V600E)-Cdk4(R24C) mouse melanoma model
Project description:We found that pigmented and amelanotic (MPNST-like) melanomas arise in the genetically engineered BRAF(V600E)-Cdk4(R24C) mouse melanoma model and even in the same animal. To explore the molecular differences between the two type of melanomas in this model we performed global gene expression profiling and pathway analysis to compare the underlying mechanisms. This information was used to identify human melanomas that resemble each type of the mouse melanomas found in the in the genetically engineered BRAF(V600E)-Cdk4(R24C) mouse melanoma model.
Project description:We used RNAseq to examine gene expression changes in thyroid tumors arising in transgenic zebrafish engineered to expression human CCDC6-RET or BRAF(V600E) oncogenes
Project description:ETV1 is amplified in a subset of melanomas. Here, we performed RNA-seq on two BRAF V600E mutant melonoma cell lines transduced with a scrambed shRNA and two individual ETV1 shRNA
Project description:Investigation of expression differences between melanomas harvested from MiniCoopR-GFP versus MiniCoopR-SETDB1 transgenic zebrafish. An eight-chip study using total RNA prepared from four distinct melanomas from zebrafish injected with MiniCoopR-GFP (control) transposon and four distinct melanomas from zebrafish injected with MiniCoopR-SETDB1 transposon. Injected animals carried a p53 loss-of-function mutation, a mutation in nacre, and an mitf:BRAF-V600E transgene. Each chip measures the expression level of 32,292 genes.
Project description:We use RNAseq to examine gene expression changes in braf;pten mouse melanomas after arising after conditional genetic inactivation of ezh2
Project description:Patients with neurofibromatosis type 1 (NF1) develop benign plexiform neurofibromas that frequently progress to become malignant peripheral nerve sheath tumors (MPNSTs). A genetically engineered mouse model that accurately models plexiform neurofibroma-MPNST progression would facilitate the identification of somatic mutations driving this process. We have previously reported that transgenic mice overexpressing the growth factor neuregulin-1 in Schwann cells (P0-GGF?3 mice) develop MPNSTs. To determine whether P0-GGF?3 mice accurately model neurofibroma-MPNST progression, cohorts of these animals were followed to death and necropsied. 94% of the mice developed multiple neurofibromas, with 70% carrying smaller numbers of MPNSTs; nascent MPNSTs were identified within neurofibromas, suggesting that these sarcomas arise from neurofibromas. Although neurofibromin expression was maintained, P0-GGF?3 MPNSTs, like human NF1-associated MPNSTs, demonstrated Ras hyperactivation. P0-GGF?3 MPNSTs also showed abnormalities in the p16INK4A-cyclin D/CDK4-Rb and p19ARF-Mdm-p53 pathways analogous to their human counterparts. Array comparative genomic hybridization (CGH) demonstrated reproducible chromosomal alterations in P0-GGF?3 MPNST cells (including universal chromosome 11 gains) and focal gains and losses affecting 39 genes previously implicated in neoplasia (e.g., Pten, Tpd52, Myc , Gli1, Xiap, Bbc3/PUMA). Array CGH also identified recurrent focal copy number variations affecting genes not previously linked to neurofibroma or MPNST pathogenesis. We conclude that P0-GGF?3 mice represent a robust model of neurofibroma-MPNST progression that can be used to identify novel genes driving neurofibroma and MPNST pathogenesis. Array CGH comparison of malignant peripheral nerve sheath tumor (MPNST) cells vs non-neoplastic Schwann cells
Project description:Among the myriad tumors analyzed to date, cutaneous malignant melanomas bear some of the highest mutational burdens. Thus, it is somewhat surprising that oncogene exclusion between is so pronounced in melanomas where there is only a single melanoma out of 366 sequenced specimens which harbors concurrent BRAF(V600E/M) and NRAS(G13R) mutations (TCGA-ES-A2NC Sample; WWW.bioportal.org), In this senario some NRAS and BRAF mutations co-expressing cells show slow growth phenotypes by under study mechanism. We used Affymetrix GeneChip Expression Arrays to detail the global programme of gene expression underlying oncogenic exclusion and identified distinct classes of up and down-regulated genes during this process.
Project description:Low grade neuroepithelial tumor is the major cause of epilepsy Low-grade neuroepithelial tumors are major causes of drug-resistant focal epilepsy. The BRAF V600E mutation is frequently observed in low grade neuroepithelial tumor and linked to poor seizure outcomes. However, its molecular role in epileptogenicity remains elusive. To understand the molecular mechanism underlying the epileptogenicity in LEAT with the BRAF V600E genetic mutation (BRAF V600E-LEAT), we conducted RNA sequencing (RNA-seq) analysis using surgical specimens of BRAF V600E-LEAT obtained and stored at a single institute. bioinformatics analysis using this dataset identified 2,134 differentially expressed genes between BRAF V600E-LEAT and control. Additionally, gene set enrichment analysis provided novel insights into the association between estrogen response-related pathways and the epileptogenicity of BRAF V600E-LEAT patients.
