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: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:Sox9 is a transcription factor expressed in most solid tumors. However, the molecular mechanisms underlying Sox9 function during tumorigenesis remain unclear. Here, using a genetic mouse model of basal cell carcinoma (BCC), the most frequent cancer in human, we show that Sox9 is expressed from the earliest step of tumor formation in a Wnt/β-catenin dependent manner. Deletion of Sox9 together with the constitutive activation of Hedgehog (HH) signaling completely prevents BCC formation and leads to a progressive loss of oncogene expressing cells. Transcriptional profiling of oncogene expressing cells with Sox9 deletion, combined with in vivo ChIP-sequencing uncovers a cancer-specific gene network regulated by Sox9 that promotes stemness, extracellular matrix (ECM) deposition and cytoskeleton remodeling while repressing epidermal differentiation. Our study identifies the molecular mechanisms regulated by Sox9 that links tumor initiation and invasion. Sox9 ChIP-seq analysis in K14CreER SmoM2 cells.
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:Prostate cancer is one of the most common malignancies and the second leading cause of death from cancer in men. The molecular mechanisms driving prostate carcinogenesis are complex; with several lines of evidence suggesting that the re-expression of conserved developmental programs play a key role. Through conditional gene targeting and organ grafting, we describe conserved roles for the transcription factor Sox9 in the initiation of both prostate organogenesis and prostate carcinogenesis in murine models. Abrogation of Sox9 expression prior to the initiation of androgen signaling blocks the initiation of prostate development. Similarly, Sox9 deletion in two genetic models of prostate cancer (TRAMP and Hi-Myc) blocks cancer initiation. Expression profiling of Sox9-null prostate epithelial cells reveals that the role of Sox9 in the initiation of prostate development may relate to its regulation of multiple cytokeratins and/or calcium-related proteins. Due to its essential role in cancer initiation, manipulation of Sox9 targets in at-risk men may prove useful in the chemoprevention of prostate cancer. Sox9 differential gene expression in prostaspheres derived from the urogenital sinus epithelium was assessed by tow-colors direct comparisons of labeled moieties. Hybridizations were performed on the Agilent (Santa Clara, CA) Whole Mouse Genome DNA microarray (mgug4122a). Sox9 targets were assessed in murine prostate epithelial cells with targeted deletion.
Project description:Aberrant expression of SOX9 in human colorectal cancer cells suggests its roles in the development of colorectal cancer. To gain insight into SOX9-mediated transcriptional regulation in colorectal cancer cells, we attempted to identify its physiological targets on a genome-scale using chromatin immunoprecipitation (ChIP) followed by sequencing (ChIP-seq) in HT-29, human colorectal cancer cells. SOX9 CHIP-seq was carried out using HT-29 cells.
Project description:Sox9 is a transcription factor expressed in most solid tumors. However, the molecular mechanisms underlying Sox9 function during tumorigenesis remain unclear. Here, using a genetic mouse model of basal cell carcinoma (BCC), the most frequent cancer in human, we show that Sox9 is expressed from the earliest step of tumor formation in a Wnt/β-catenin dependent manner. Deletion of Sox9 together with the constitutive activation of Hedgehog (HH) signaling completely prevents BCC formation and leads to a progressive loss of oncogene expressing cells. Transcriptional profiling of oncogene expressing cells with Sox9 deletion, combined with in vivo ChIP-sequencing uncovers a cancer-specific gene network regulated by Sox9 that promotes stemness, extracellular matrix (ECM) deposition and cytoskeleton remodeling while repressing epidermal differentiation. Our study identifies the molecular mechanisms regulated by Sox9 that links tumor initiation and invasion.