PTEN-deficient intestinal stem cells initiate intestinal polyposis
Ontology highlight
ABSTRACT:
ORGANISM(S): Mus musculus
PROVIDER: GSE6078 | GEO | 2006/11/18
SECONDARY ACCESSION(S): PRJNA97573
REPOSITORIES: GEO
Similar Datasets
Project description:Intestinal polyposis, a precancerous neoplasia, results primarily from an abnormal increase in the number of crypts. Crypts contain intestinal stem cells (ISCs). Thus intestinal polyposis provides an ideal condition for studying stem cell involvement in polyp/tumor formation. Using a conditional knock-out mouse model, we found that the tumor suppressor Phosphatase of Tension homolog (PTEN) governs the proliferation rate and number of ISCs and loss of PTEN results in an excess of ISCs. In PTEN mutants, excess ISCs initiate de-novo crypt formation and crypt fission, recapitulating crypt production in fetal/neonatal intestine. Microarray studies were used to profile the changes in gene expression that occurred when PTEN was knocked out in the intestine. Experiment Overall Design: A conditional PTEN mutant allele [Groszer, M. et al. Negative regulation of neural stem/progenitor cell proliferation by the Pten tumor suppressor gene in vivo. Science 294, 2186-2189 (2001).] was combined with in interferon inducible Mx1-Cre [Kuhn, R., Schwenk, F., Aguet, M. & Rajewsky, K. Inducible gene targeting in mice. Science 269, 1427-1429 (1995).] to enable PTEN to be deleted from the intestine by administration of polyinosinicâ??polycytidylic acid (Poly I:C). PolyI:C was administered at weaning (every other day, five times total) to three PTEN mutant (Mx1-Cre positive:PTENfx/fx) and two control (Mx1-Cre negative:PTENfx/+) animals. Intestinal polyps (from PTEN mutants) and equivalent regions of intestine (from controls) were isolated 30 days after the final polyI:C injection. Microarray analysis compared the gene expression profiles of PTEN mutant polyps and control intestines. Genes were considered up-regulated or down-regulated if all of the following conditions were met: 1) There was at least a two-fold change in the average probe signal measured between controls and mutants; 2) There was no overlap between the range of mutant and control data; and 3) The control mean was outside the 95% confidence interval of the PTEN-mutant mean.
2008-06-14 | E-GEOD-6078 | biostudies-arrayexpress
Project description:Oncogenic mutations that drive colorectal cancer can be present in healthy intestines for long periods without overt consequence. Mutation of Adenomatous polyposis coli (Apc), the most common initiating event in conventional adenomas, activates Wnt signaling, hence conferring fitness on mutant intestinal stem cells (ISCs). Apc mutations may occur in ISCs that arose by routine self-renewal or by dedifferentiation of their progeny. Although ISCs of these different origins are fundamentally similar, it is unclear if both generate tumours equally well in uninjured intestines. Also unknown is whether cis-regulatory elements are substantively modulated upon Wnt hyperactivation or as a feature of subsequent tumours. Here, we show in two mouse models that adenomas are not an obligatory outcome of Apc deletion in either ISC source but require proximity of mutant intestinal crypts. Reduced crypt density abrogates, and aggregation of mutant colonic crypts augments, adenoma formation. Moreover, adenoma-resident ISCs open chromatin at thousands of enhancers that are inaccessible in Apc-null ISCs not associated with adenomas. These cis-elements explain adenoma-selective gene activity and persist, with little further expansion of the repertoire, as other oncogenic mutations accumulate. Thus, cooperativity between neighbouring mutant crypts and new accessibility at specific enhancers are key steps early in intestinal tumourigenesis.
2024-11-15 | GSE241380 | GEO
Project description:Oncogenic mutations that drive colorectal cancer can be present in healthy intestines for long periods without overt consequence. Mutation of Adenomatous polyposis coli (Apc), the most common initiating event in conventional adenomas, activates Wnt signaling, hence conferring fitness on mutant intestinal stem cells (ISCs). Apc mutations may occur in ISCs that arose by routine self-renewal or by dedifferentiation of their progeny. Although ISCs of these different origins are fundamentally similar, it is unclear if both generate tumours equally well in uninjured intestines. Also unknown is whether cis-regulatory elements are substantively modulated upon Wnt hyperactivation or as a feature of subsequent tumours. Here, we show in two mouse models that adenomas are not an obligatory outcome of Apc deletion in either ISC source but require proximity of mutant intestinal crypts. Reduced crypt density abrogates, and aggregation of mutant colonic crypts augments, adenoma formation. Moreover, adenoma-resident ISCs open chromatin at thousands of enhancers that are inaccessible in Apc-null ISCs not associated with adenomas. These cis-elements explain adenoma-selective gene activity and persist, with little further expansion of the repertoire, as other oncogenic mutations accumulate. Thus, cooperativity between neighbouring mutant crypts and new accessibility at specific enhancers are key steps early in intestinal tumourigenesis.
2024-11-10 | GSE281056 | GEO
Project description:Oncogenic mutations that drive colorectal cancer can be present in healthy intestines for long periods without overt consequence. Mutation of Adenomatous polyposis coli (Apc), the most common initiating event in conventional adenomas, activates Wnt signaling, hence conferring fitness on mutant intestinal stem cells (ISCs). Apc mutations may occur in ISCs that arose by routine self-renewal or by dedifferentiation of their progeny. Although ISCs of these different origins are fundamentally similar, it is unclear if both generate tumours equally well in uninjured intestines. Also unknown is whether cis-regulatory elements are substantively modulated upon Wnt hyperactivation or as a feature of subsequent tumours. Here, we show in two mouse models that adenomas are not an obligatory outcome of Apc deletion in either ISC source but require proximity of mutant intestinal crypts. Reduced crypt density abrogates, and aggregation of mutant colonic crypts augments, adenoma formation. Moreover, adenoma-resident ISCs open chromatin at thousands of enhancers that are inaccessible in Apc-null ISCs not associated with adenomas. These cis-elements explain adenoma-selective gene activity and persist, with little further expansion of the repertoire, as other oncogenic mutations accumulate. Thus, cooperativity between neighbouring mutant crypts and new accessibility at specific enhancers are key steps early in intestinal tumourigenesis.
2024-11-15 | GSE241382 | GEO
Project description:Oncogenic mutations that drive colorectal cancer can be present in healthy intestines for long periods without overt consequence. Mutation of Adenomatous polyposis coli (Apc), the most common initiating event in conventional adenomas, activates Wnt signaling, hence conferring fitness on mutant intestinal stem cells (ISCs). Apc mutations may occur in ISCs that arose by routine self-renewal or by dedifferentiation of their progeny. Although ISCs of these different origins are fundamentally similar, it is unclear if both generate tumours equally well in uninjured intestines. Also unknown is whether cis-regulatory elements are substantively modulated upon Wnt hyperactivation or as a feature of subsequent tumours. Here, we show in two mouse models that adenomas are not an obligatory outcome of Apc deletion in either ISC source but require proximity of mutant intestinal crypts. Reduced crypt density abrogates, and aggregation of mutant colonic crypts augments, adenoma formation. Moreover, adenoma-resident ISCs open chromatin at thousands of enhancers that are inaccessible in Apc-null ISCs not associated with adenomas. These cis-elements explain adenoma-selective gene activity and persist, with little further expansion of the repertoire, as other oncogenic mutations accumulate. Thus, cooperativity between neighbouring mutant crypts and new accessibility at specific enhancers are key steps early in intestinal tumourigenesis.
2024-11-15 | GSE241383 | GEO
Project description:Paneth cells are antimicrobial peptide-secreting cells located at the base of the crypts of the small intestine. The proteome of Paneth cells is not well defined because of their co-existence with stem cells making it difficult to culture Panth cells alone in vitro. Using a simplied toluidine blue O method for staining mouse intestinal tissue, laser capture microdissection (LCM) to isolate cells from the crypt region and surfactant assisted one pot protein digestion, we identified more than 1,300 proteins from crypts equivalent to 18,000 cells. Compared with the proteomes of villi and smooth muscle regions, the crypt proteome is highly enriched in defensins, lysozymes and other antimicrobial peptides that are characteristic of Paneth cells. The sensitivity of the LCM-based proteomics approach was also assessed using a smaller number of cell equivalent tissues, a comparable proteomic coverage can be achieved with 3,600 cells. This work is the first proteomics study of intestinal tissue enriched with Paneth cells. The simplied workflow enables profiling of Paneth cell associated pathological changes at the proteome level directly from frozen intestinal tissue. It may also be useful for proteomics studies of other spatially resolved cell types from other tissues.
2022-10-12 | PXD034143 | Pride
Project description:Regenerative cell state dynamics are under-characterized. Intestinal damage prompts reprogramming into revival stem cells (revSCs) that reconstitute Lgr5+ intestinal stem cells (ISCs). Here, single nuclear multiomics of crypts regenerating from irradiation shows revSC epigenetic profiles overlap with ISCs and differentiated lineages. RevSC genes themselves are accessible throughout homeostatic epithelia, while damage-induced crypt remodelling converges on the Hippo and TGFβ pathway that is transiently activated in the crypt and directly induces functional revSCs. Combinatorial analysis of gene expression suggests multiple sources of revSCs, and we show TGFb can reprogram Enterocytes, Goblet, and Paneth cells into revSCs, further demonstrating individual revSCs form organoids. Despite this, loss of TGFβ signalling yielded mild regenerative defects, whereas interference in both Hippo and TGFβ led to rapid intestinal collapse with no detectable revSCs or ISCs. Regenerative signalling is thus poised for activation by a compensatory system of crypt-localized, transient morphogen cues that support robust intestinal regeneration.
2024-08-19 | GSE230766 | GEO
Project description:Intestinal epithelial stem cells (ISCs) are the focus of recent intense study. Current in vitro models rely on supplementation with the Wnt agonist R-spondin1 to support robust growth, ISC self-renewal, and differentiation. Intestinal subepithelial myofibroblasts (ISEMFs) are important supportive cells within the ISC niche. We hypothesized that co-culture with ISEMF enhances the growth of ISCs in vitro and allows for their successful in vivo implantation and engraftment. ISC-containing small intestinal crypts, FACS-sorted single ISCs, and ISEMFs were procured from C57BL/6 mice. Crypts and single ISCs were grown in vitro into enteroids, in the presence or absence of ISEMFs. ISEMFs enhanced the growth of intestinal epithelium in vitro in a proximity-dependent fashion, with co-cultures giving rise to larger enteroids than monocultures. Co-culture of ISCs with supportive ISEMFs relinquished the requirement of exogenous R-spondin1 to sustain long-term growth and differentiation of ISCs. Mono- and co-cultures were implanted subcutaneously in syngeneic mice. Co-culture with ISEMFs proved necessary for successful in vivo engraftment and proliferation of enteroids; implants without ISEMFs did not survive. ISEMF whole transcriptome sequencing and qPCR demonstrated high expression of specific R-spondins, well-described Wnt agonists that supports ISC growth. Specific non-supportive ISEMF populations had reduced expression of R-spondins. The addition of ISEMFs in intestinal epithelial culture therefore recapitulates a critical element of the intestinal stem cell niche and allows for its experimental interrogation and biodesign-driven manipulation. Two samples of intestinal subepithelial myofibroblasts were used in this study.
2013-12-20 | E-GEOD-52402 | biostudies-arrayexpress
Project description:Intestinal stem cells (ISCs) residing in the crypts are critical for the continual self-renewal and rapid recovery of intestinal epithelium. The regulatory mechanism of ISCs is not fully understood. Here we report that CREPT, a recently identified tumor-promoting gene, is preferably expressed in the crypts, where the ISCs reside, but not in the villi. To explore the function of CREPT in ISCs, we isolated crypts to perform Next generation sequencing.
2020-11-08 | GSE143695 | GEO
Project description:The small intestine is responsible for nutrient absorption and it is one of the most important interfaces between the environment and our body. During aging, changes in the structure of the epithelium lead to food malabsorption and reduced barrier function thus increasing disease risk in aging. The molecular drivers of these alterations remain poorly understood. Here, we compared the proteomes of small intestinal crypts from mice across different anatomical regions and age groups. We found that aging alters epithelial immune responses, metabolic networks and stem cell proliferation, and it is accompanied by a region-dependent skewing in the cellular composition of the intestinal epithelium. Of note, a short period of dietary restriction followed by re-feeding partially restores the epithelium to a youthful state by promoting the differentiation of intestinal stem cells (ISCs) towards the secretory lineage. Using in vitro and in vivo studies, we identify Hmgcs2 (3-hydroxy-3-methylglutaryl-CoA synthetase 2) – the rate limiting enzyme in the synthesis of ketone bodies – as a modulator of ISCs differentiation, which responds to dietary changes. This study provides an atlas of age-dependent proteome changes in defined regions of the intestinal epithelium and characterizes how young and old mice adapt to drastic changes of diet, such as dietary restriction and re-feeding.
2020-04-29 | PXD014311 | Pride