Project description:Synovial sarcoma is a deadly soft-tissue malignancy with a predilection for adolescents and young adults. Mice recapitulate synovial sarcomagenesis from expression of SS18-SSX2 in certain cells. Concomitant expression of a stabilized form of beta-catenin enhances synovial sarcomagenesis and expands the potential cells of origin. Mice bearing conditional expression of SS18-SSX2 from the Rosa26 locus and conditional excision of the 3rd exon of beta-catenin, each activated in the leg by Cre-recombinase expressed from an adeno-associated viral vector, formed large tumors at brief latency.
Project description:Synovial sarcoma is a deadly soft-tissue malignancy with a predilection for adolescents and young adults. Mice recapitulate synovial sarcomagenesis from expression of SS18-SSX2 in certain cells. Concomitant expression of a stabilized form of beta-catenin enhances synovial sarcomagenesis and expands the potential cells of origin.
Project description:Myeloid cell lines (K562 and HEL) were treated overnight with CHIR99021 or a vehicle control (DMSO). CHIR99021 treatment inhibits GSK3B within the destruction complex functioning in Wnt/beta-catenin signalling pathway, thereby preventing beta-catenin degradation and promoting its stabilization. Following the overnight incubation, beta-catenin RIP (RNA immunoprecipitation) was performed in both K562 and HEL cells. RNA samples obtained from beta-catenin RIP in these cells were then sequenced to identify beta-catenin-associated RNAs under CHIR99021 treatment compared to basal conditions (DMSO control).
Project description:Deregulation of canonical Wnt/beta-catenin pathway is one of the earliest events in the pathogenesis of colon cancer. Mutations in APC or CTNNB1 (beta-catenin gene) are highly frequent in colon cancer and cause aberrant stabilization of b-catenin, which activates the transcription of Wnt target genes by binding to chromatin via the TCF/LEF transcription factors. Here we report an integrative analysis of genome-wide chromatin occupancy of b-catenin by chromatin immunoprecipitation coupled with high-throughput sequencing (ChIP-seq) and gene expression profiling by microarray analysis upon RNAi-mediated knockdown of beta-catenin in colon cancer cells (GSE53656). Immunoprecipitated samples from human colon cancer SW480 cells with antibodies against beta-catenin and control IgG respectively were used for ChIP-seq experiments.
Project description:Gain-of-function mutations in exon 3 of beta-catenin (CTNNB1) are specific for Wilms' tumors that have lost WT1, but 50% of WT1-mutant cases lack such "hot spot" mutations. To ask whether stabilization of beta-catenin might be essential after WT1 loss, and to identify downstream target genes, we compared expression profiles in WT1-mutant versus WT1 wild-type Wilms' tumors. Supervised and nonsupervised hierarchical clustering of the expression data separated these two classes of Wilms' tumor. The WT1-mutant tumors overexpressed genes encoding myogenic and other transcription factors (MOX2, LBX1, SIM2), signaling molecules (TGFB2, FST, BMP2A), extracellular Wnt inhibitors (WIF1, SFRP4), and known beta-catenin/TCF targets (FST, CSPG2, CMYC). Beta-Catenin/TCF target genes were overexpressed in the WT1-mutant tumors even in the absence of CTNNB1 exon 3 mutations, and complete sequencing revealed gain-of-function mutations elsewhere in the CTNNB1 gene in some of these tumors, increasing the overall mutation frequency to 75%. Lastly, we identified and validated a novel direct beta-catenin target gene, GAD1, among the WT1-mutant signature genes. These data highlight two molecular classes of Wilms' tumor, and indicate strong selection for stabilization of beta-catenin in the WT1-mutant class. Beta-Catenin stabilization can initiate tumorigenesis in other systems, and this mechanism is likely critical in tumor formation after loss of WT1. Experiment Overall Design: Identification of WNT/Beta-Catenin or WT1 target genes. 39 individual samples.
Project description:We used microarrays to detail the gene expression profile during WAT -beige transition by treatment of beta adrenergic receptor agonist .
Project description:Genome wide expression profiling to determine the overlap of Affymetrix-signals with SOLID sequencing RNA was extracted using the Qiagen RNeasy kit following the manufacturers guidelines, arrays were prepared and hybridized following the Affymetrix protocol.