Project description:SOX9 is critical for prostate development and is implicated in prostate cancer, we used transcriptome profiling in combination with SOX9 ChIP-seq to identify genes and pathways it regulates in normal or neoplastic epithelium. We used microarrays to detail the global programme of gene expression in TMPRSS2/ERG fusion positive prostate cancer cell line with high basal expression of SOX9 by comparing the expression changes between SOX9 knockdown versus control.
Project description:SOX9 is critical for prostate development and is implicated in prostate cancer, we used SOX9 ChIP-seq in combination with transcriptome profiling to identify genes and pathways it regulates in normal or neoplastic epithelium.
Project description:Mammalian intestinal epithelium stem cells (IESCs) and their daughter cells require the participation of DNA methylation and the transcription factor Sox9 for proliferation and differentiation. Combining methylated DNA immunoprecipitation with microarray hybridization, we demonstrate that hypomethylation in promoter participates in the aberrant formation of crypts in diabetic db/db mice through ectopic Wnt signaling. More importantly, increased expression of Sox9 is accompanied by the loss of methylation in its promoter in IESCs. Using ChIP-seq analysis for Sox9 in IESCs, we demonstrate that Sox9 primarily targets the enhancers of Wnt signaling pathway-related genes. Sox9 is not only predominately acting as a transcriptional activator at proximal enhancer but also as a potential transcriptional inhibitor at distant enhancer. Lack of Sox9 transcriptional activation in specific repressors of Wnt signaling pathway results in loss of intrinsic inhibitory action and ultimately produces over-activation of this pathway in diabetes mellitus.
Project description:The Wnt signaling pathway is playing a crucial role during development and adult tissue homeostasis. However, the tissue and cell type-specific regulation of Wnt pathway activity remains incompletely understood. Here we identify FOXB2, an uncharacterized forkhead box family transcription factor, as a potent activator of Wnt signaling in normal and cancer cells. Proximity-dependent biotinylation assay (BioID) coupled with mass spectrometry identified transcriptional co-regulators required for FOXB2-dependent Wnt activation.
Project description:Mammalian intestinal epithelium stem cells (IESCs) and their daughter cells require the participation of DNA methylation and the transcription factor Sox9 for proliferation and differentiation. Combining methylated DNA immunoprecipitation with microarray hybridization, we demonstrate that hypomethylation in promoter participates in the aberrant formation of crypts in diabetic db/db mice through ectopic Wnt signaling. More importantly, increased expression of Sox9 is accompanied by the loss of methylation in its promoter in IESCs. Using ChIP-seq analysis for Sox9 in IESCs, we demonstrate that Sox9 primarily targets the enhancers of Wnt signaling pathway-related genes. Sox9 is not only predominately acting as a transcriptional activator at proximal enhancer but also as a potential transcriptional inhibitor at distant enhancer. Lack of Sox9 transcriptional activation in specific repressors of Wnt signaling pathway results in loss of intrinsic inhibitory action and ultimately produces over-activation of this pathway in diabetes mellitus.
Project description:The Wnt pathway plays a central role in controlling differentiation of epithelial tissues; when Wnt is on, differentiation is suppressed, but when Wnt is off, differentiation is allowed to proceed. Based on this concept, we hypothesized that expression of key genes in the Wnt pathway are suppressed in the human airway epithelium under the stress of cigarette smoking, a stress associated with dysregulation of the differentiated state of the airway epithelium. For this purpose, HG-U133 Plus 2.0 microarrays were used to assess the expression of Wnt-related genes in the small airway (10th-12th generation) epithelium (SAE) obtained via bronchoscopy and brushing of healthy nonsmokers (n=47), healthy smokers (n=58), and smokers with established COPD (n=22). With expression defined as present in >20% of samples, microarray analysis demonstrated that 35 of 57 known Wnt-related genes are expressed in the adult SAE. Wnt pathway downstream targets β-catenin (p<0.05) and the transcription factor 7-like 1 were down-regulated in healthy smokers, and smokers with COPD, as were a number of Wnt target genes, including VEGFA, CCND1, MMP7, CLDN1, SOX9, RHOU (all p<0.05 compared to healthy nonsmokers). As a mechanism to explain this broad, smoking-induced suppression of the Wnt pathway, we assessed expression of the DKK and SFRP families, extracellular regulators that suppress the Wnt pathway. Among these, secreted frizzled-related protein 2 (SFRP2), was up-regulated 4.3-fold (p<0.0001) in healthy smokers and 4.9-fold (p<0.0001) in COPD smokers, an observation confirmed by TaqMan Real-time PCR. AT the protein levels, Western analysis demonstrated SFRP2 up-regulation, and immunohistochemistry demonstrated that the smoking-induced SFRP2 upregulation occurred in differentiated ciliated cells. Finally, cigarette smoke extract mediated up-regulation of SFRP2 and downregulation of Wnt target genes in airway epithelial cells in vitro. These observations are consistent with the hypothesis that the Wnt pathway plays a role in airway epithelial cell differentiation in the adult human airway epithelium, with smoking associated with down-regulation of Wnt pathway, contributing to the dysregulation of airway epithelial differentiation observed in the smoking-related airway disorders. Affymetrix arrays were used to assess gene expression data of genes in the Wnt pathway in small airway epithelium obtained by fiberoptic bronchoscopy of 47 healthy non-smokers and 58 healthy smokers and 22 smokers with COPD.
Project description:DNAPK was identified as the most significantly expressed kinase associated with metastatic progression in high-risk prostate cancer. GSEA analysis on DNAPK knockdwon samples and on patient data nominated Wnt signaling as the top pathway associated with DNAPK Our data indicates that DNAPK regulates Wnt signaling pathway.