Project description:ETS transcription factors have recently emerged as important elements in the pathogenesis of prostate cancer (PCa). ETS gene rearrangements leading to over-expression of ETS factors, like ERG, ETV1 and ETV4, are found in about 50% of prostate tumors. While the oncogenic potential of translocated ETS has been demonstrated in several contexts, the impact of endogenously expressed ETS factors on prostate tumorigenesis has been largely overlooked. Here we show that the epithelial-specific ETS factor ESE3, which is normally expressed in basal prostate epithelial (PrE) cells and frequently down-regulated in prostate tumors, serves as gatekeeper to maintain cell differentiation and its down-regulation leads to the acquisition of mesenchymal, stem cell (SC) and tumorigenic properties. ESE3 exerts this function by regulating critical genes involved in the epithelial to mesenchymal transition (EMT) and cell “stemness” and maintaining the equilibrium between cell differentiation and proliferation. Loss of ESE3 may be an important step in prostate tumorigenesis. Keywords: prostate epithelial cells, prostate cancer, gene expression profiling, ETS genes, EMT, cancer stem cells
Project description:PDEF(Prostate Derived Ets factor) is a member of Ets transcription factor with specific expression in Prostate. We identified target genes for PDEF in prostate cancer cell line PC-3 using Affymetrix Genechip Microarray technology. Keywords: target gene identification for transcription factor
Project description:This work was conducted to identify shared and specific target genes of different ETS transcription factor rearrangements in prostate cancer. Potential target genes were identified by differential gene expression analysis of primary tumor samples with ETS rearrangements, and validated by ETS silencing in prostate cancer cell lines. The series consists of 50 primary tumor samples from a consecutive series of 200 clinically localized cancers treated with radical prostatectomy at the Portuguese Oncology Institute, Porto, Portugal. The series is enriched in tumors with ETS transcription factor rearrangements
Project description:This work was conducted to identify shared and specific target genes of different ETS transcription factor rearrangements in prostate cancer. Potential target genes were identified by differential gene expression analysis of primary tumor samples with ETS rearrangements, and validated by ETS silencing in prostate cancer cell lines.
Project description:Deregulated expression of ETS transcription factors with oncogenic and tumor suppressor function occurs frequently in prostate cancer leading to profound alterations of the cancer transcriptome. By integrating genomic and functional studies we identified key targets of the aberrantly expressed ETS factors, ERG and ESE3. Altered expression of ETS factors led to the induction of the polycomb group protein EZH2 and silencing of the tumor suppressor Nkx3.1. Nkx3.1 was controlled by ERG and ESE3 both directly via binding to ETS binding sites in the gene promoter and indirectly via EZH2-induced histone H3K27 methylation. This may represent a general mechanism linking aberrantly expressed ETS with deregulation of epigenetic pathways and global reprogramming of the prostate epithelial cell transcriptome in prostate tumorigenesis. Keywords: prostate cancer, gene expression profiling, ETS genes In this study we show that deregulated expression of ETS factors with opposite functions is highly frequent in prostate cancer. Our study uncovers a previously unrecognized link between aberrant expression of ETS factors, deregulation of epigenetic pathways and silencing of tumor suppressor genes in prostate cancer and shows that partially distinct transcriptional programs are associated with different ETS gene expression patterns. The presence of distinct prostate cancer subgroups with different biological features may have important clinical implications and suggests that assessment of ETS expression levels might be useful to distinguish tumors with different clinical outcome.
Project description:Translocations of ETS transcription factors are driver mutations in diverse cancers. We investigated the genomic network of the ETS fusion EWS/FLI1 in Ewing's sarcoma (ESFT) as a model of ETS-driven tumorigenesis. ChIP-Seq and transcriptional analysis identified E2F3 as a principle co-factor of EWSFLI1 defining functionally distinct gene sets. While EWS/FLI1 binding independent of E2F3 predominantly associated with repressed differentiation genes, significant co-localization with E2F3 was discovered at proximal promoters of activated growth-related genes. Thus, EWS/FLI1 promotes oncogenesis by simultaneously perturbing differentiation state and augmenting the expression of genes co-regulated by E2F3. Integration of additional E2F3 and ERG localization data from prostate cancer containing TMPRSS2/ERG verified that the ETS-E2F module is also found in prostate cancer and may be of general relevance to ETS driven cancers. Timecourse with 6 timepoints of a doxicyclin inducible EWS-FLI1 knockdown in the A673 Ewing's Sarcoma celline
Project description:Deregulated expression of ETS transcription factors with oncogenic and tumor suppressor function occurs frequently in prostate cancer leading to profound alterations of the cancer transcriptome. By integrating genomic and functional studies we identified key targets of the aberrantly expressed ETS factors, ERG and ESE3. Altered expression of ETS factors led to the induction of the polycomb group protein EZH2 and silencing of the tumor suppressor Nkx3.1. Nkx3.1 was controlled by ERG and ESE3 both directly via binding to ETS binding sites in the gene promoter and indirectly via EZH2-induced histone H3K27 methylation. This may represent a general mechanism linking aberrantly expressed ETS with deregulation of epigenetic pathways and global reprogramming of the prostate epithelial cell transcriptome in prostate tumorigenesis. Keywords: prostate cancer, gene expression profiling, ETS genes