Homo sapiens
Ontology highlight
ABSTRACT:
PROVIDER: PRJNA149987 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:Hyperplastic Polyposis Syndrome (HPS) is a condition associated with multiple serrated polyps, and an increased risk of colorectal cancer (CRC). The majority of CRCs arising in HPS show a CpG island methylator phenotype (CIMP) that encompasses several common tumor suppressor genes, including regulators of DNA mismatch repair, and negative regulators of Wnt signaling. However, little is currently known about the CIMP status of premalignant polyp tissue in HPS or the temporal changes in CIMP profile associated with transition to malignancy. Using genomescale DNA methylation analysis of HPS polyp and disease-free tissue, we identified widespread coordinated DNA methylation changes, common to all HPS polyps examined. The majority of consistent changes involve low-intermediate (10-50%) methylation and include several tumour suppressor genes, including multiple negative regulators of Wnt signalling (SFRP-1, -2, -4, -5) and cell cycle regulation (eg. RASSF1). We also confirmed selective methylation of the RUNX1, CHFR, CDKN2A, and MLH-1 promoters previously described in HPS, but found no evidence for methylation of DNA mismatch repair genes MGMT or MSH-2 in premalignant polyps. Consistent and widespread methylation of the WT-1 tumour suppressor gene also appears to be a common feature of HPS. Interestingly, where tested the majority of methylation identified was localised to a single allele within the polyp tissue. These findings reveal that premalignant HPS is associated with coordinated, widespread intermediate levels of gene promoter methylation in several TS genes implicated in CRC, primarily restricted to one of two alleles. Transition to malignancy appears to be associated with widespread elevation of methylation at these sites. These findings warrant a further investigation of the potential for future development of novel methylation-based molecular assays for the prediction of HPS cases likely to transition to malignancy.
2014-12-01 | GSE34068 | GEO
Project description:The tumor suppressor gene adenomatous polyposis coli (APC) is mutated in most colorectal cancers (CRC) resulting in constitutive Wnt activation. To understand the Wnt-activating mechanism of APC mutation, we applied CRISPR/Cas9 technology to engineer various APC-truncated isogenic lines. We find that the β-catenin inhibitory domain (CID) in APC represents the threshold for pathological levels of Wnt activation and tumor transformation. Mechanistically, CID-deleted APC truncation promotes β-catenin deubiquitination through reverse binding of β-TrCP and USP7 to the destruction complex. USP7 depletion in APC-mutated CRC inhibits Wnt activation by restoring β-catenin ubiquitination, drives differentiation and suppresses xenograft tumor growth. Finally, the Wnt-activating role of USP7 is specific to APC mutations, thus can be used as tumor-specific therapeutic target for most CRCs.
2017-11-09 | PXD007947 | Pride
Project description:The first step in the development of colorectal cancer (CRC) is the aberrant hyperactivation of the Wnt signaling pathway, predominantly caused by inactivating mutations in the adenomatous polyposis coli (APC) gene encoding an essential tumor suppressor. In order to identify genes affected by Apc loss, expression profiling of intestinal epithelium isolated from mice harboring the conditional allele of the gene was performed.
2019-11-01 | E-MTAB-6915 | biostudies-arrayexpress
Project description:The Adenomatous Polyposis Coli (APC) tumor suppressor is mutated in the vast majority of human colorectal cancers (CRC) and leads to deregulated Wnt signaling. To determine whether Apc disruption is required for tumor maintenance, we developed a mouse model of CRC whereby Apc can be conditionally suppressed using a doxycycline-regulated shRNA. Apc suppression produces adenomas in both the small intestine and colon that, in the presence of Kras and p53 mutations, can progress to invasive carcinoma. In established tumors, Apc restoration drives rapid and widespread tumor-cell differentiation and sustained regression without relapse. Tumor regression is accompanied by the re-establishment of normal crypt-villus homeostasis, such that once aberrantly proliferating cells reacquire self-renewal and multi-lineage differentiation capability. Our study reveals that CRC cells can revert to functioning normal cells given appropriate signals, and provide compelling in vivo validation of the Wnt pathway as a therapeutic target for treatment of CRC Analysis of RNA isolated from colon polyps that presented in shAPC or shAPC/Kras mice as compared to shRenilla (neutral) mouse colon mucosa
2015-06-18 | E-GEOD-67186 | biostudies-arrayexpress
Project description:Tumor Associated Calcium Signal Transducer 2 (TACSTD2) is one of the cancer-related genes whose overexpression correlates with tumor progression and invasiveness in human colorectal cancer. TACSTD2 gene encodes for a transmembrane glycoprotein TROP2, which is implicated in altered expression of epithelial-mesenchymal transition (EMT) markers and may play a role in metastasis formation. To monitor the onset of TROP2 in hyperplastic cells and its effect on aberrant signaling potentially leading to tumor growth, we isolated epithelial cells from the mouse small intestine 7 days after disruption of the Adenomatous polyposis coli (Apc) gene. Loss of APC tumor suppressor function is the most common initial step in the development of colon cancer in humans. In the mice, the epithelial hyperproliferation occurs within a few days after Apc disruption, accompanied by the formation of ectopic crypts, followed by the formation of microadenomas over time. We performed expression profiling of Trop2+ and Trop2- hyperproliferating cells and, in addition, non-proliferating cells of the intestinal epithelium, including predominantly differentiated cells.
2022-11-29 | E-MTAB-11377 | biostudies-arrayexpress
Project description:Expression data from hyperplastic polyps and normal colonic mucosa from patients with familial and sporadic hyperplastic polyposis syndrome (HPPS). We aim to characterize at a molecular level a cohort of hyperplastic lesions from HPPS patients with and without family history.
2010-12-01 | GSE19963 | GEO
Project description:The Adenomatous Polyposis Coli (APC) tumor suppressor is mutated in the vast majority of human colorectal cancers (CRC) and leads to deregulated Wnt signaling. To determine whether Apc disruption is required for tumor maintenance, we developed a mouse model of CRC whereby Apc can be conditionally suppressed using a doxycycline-regulated shRNA. Apc suppression produces adenomas in both the small intestine and colon that, in the presence of Kras and p53 mutations, can progress to invasive carcinoma. In established tumors, Apc restoration drives rapid and widespread tumor-cell differentiation and sustained regression without relapse. Tumor regression is accompanied by the re-establishment of normal crypt-villus homeostasis, such that once aberrantly proliferating cells reacquire self-renewal and multi-lineage differentiation capability. Our study reveals that CRC cells can revert to functioning normal cells given appropriate signals, and provide compelling in vivo validation of the Wnt pathway as a therapeutic target for treatment of CRC
2015-06-18 | GSE67186 | GEO
Project description:Expression profiling is a well established tool for the genome-wide analysis of the transcriptional activity of human neoplasia. However, the high sensitivity of this approach combined with the well-known cellular and molecular heterogeneity of cancer often result in extremely complex and extended expression signatures of difficult functional interpretation. The majority of sporadic colorectal cancer cases are triggered by mutations in the APC tumor suppressor gene leading to constitutive activation of the Wnt/b-catenin signaling pathway and adenoma formation. Notwithstanding this common genetic basis, colorectal cancers are very heterogeneous in their degree of differentiation, growth rate and malignant potential. Here, we applied cross-species comparison of expression profiles of intestinal polyps derived from hereditary colorectal cancer patients carrying APC germline mutations, and from a mouse model carrying a targeted inactivating mutation in the mouse homologue Apc. This comparative approach resulted in the establishment of a conserved signature encompassing 166 genes differentially expressed between adenomas and normal intestinal mucosa in both species. Functional analysis of the conserved genes revealed a general increase in cell proliferation and the activation of the Wnt/b-catenin signal transduction pathway, as expected from the selection of APC/Apc-mutant intestinal adenomas. Moreover, the conserved signature is able to resolve expression profiles from hereditary polyposis patients carrying APC germline mutations from those with bi-allelic incativation of the MYH gene. Keywords: normal versus tumor comparison; compare expression profiles from microdissected samples with distinct germline mutations (FAP vs. MAP). Here, we report the expression profiles from normal and intestinal adenomatous tissue from FAP (familial adenomatous polyposis) and MAP (MUTY-associated polyposis) patients with established APC and MUTY germline mutations. Total RNA samples were obtianed by laser capture microdissection.
2008-04-01 | E-GEOD-9689 | biostudies-arrayexpress
Project description:The first step in the development of human colorectal cancer (CRC) is the aberrant hyperactivation of the Wnt signaling pathway, predominantly caused by inactivating mutations in the adenomatous polyposis coli (APC) gene encoding an essential tumor suppressor. In order to identify genes affected by Apc loss, expression profiling of intestinal epithelium isolated from mice harboring the conditional allele of the gene was performed. The gene encoding transcriptional factor msh homeobox 1 (Msx1) displayed robust upregulation upon Apc inactivation. Subsequently, the expression pattern of human MSX1 was examined in a collection of colonic tumors. The MSX1 mRNA level was increased in all types of human intestinal neoplasia tested. In order to identify genes affected by MSX1 loss, expression profiling of human colorectal cancer cells SW620 upon MSX1 gene depletion was performed.
2019-11-01 | E-MTAB-6928 | biostudies-arrayexpress
Project description:The first step in the development of human colorectal cancer is the aberrant hyperactivation of the Wnt signaling pathway, predominantly caused by inactivating mutations in the adenomatous polyposis coli (Apc) gene encoding an essential tumor suppressor. The gene encoding transcriptional factor msh homeobox 1 (Msx1) displayed robust upregulation upon Apc inactivation in intestinal epithelium isolated in mice harboring the conditional allele of the Apc gene. To identify the gene signature in the small intestine upon Msx1 depletion, small intestinal epithelium from mice harboring conditional alleles of Apc and Msx1 was isolated and the gene expression profile was compared with control mice harboring the conditional allele of Apc only.
2019-11-01 | E-MTAB-6930 | biostudies-arrayexpress