Similar Datasets
Project description:β-catenin-dependent canonical Wnt signaling plays a plethora of roles in organ development, tissue homeostasis and cancer. Here we identified an upstream enhancer of Ctnnb1 - ieCtnnb1 - that controls intestinal homeostasis. ieCtnnb1 is specifically active in crypts of small and large intestines. Single-cell sequencing revealed that ieCtnnb1 knockout (ieCtnnb1KO) biased epithelial composition and functions of small intestinal crypts – leaning toward absorptive functions at the expense of secretive roles. Deletion of ieCtnnb1 hampered epithelial turnovers in physiologic and regenerative conditions. In contrast, deletion of ieCtnnb1 prevents occurrence and progression of Wnt/β-catenin driving colorectal cancers. The human ieCTNNB1 specifically drives reporter in intestinal crypts and contains a SNP that is associated with CTNNB1 expression levels in human gastrointestinal epithelia. The enhancer activity of ieCTNNB1 in colorectal cancer tissues is higher than that in adjacent normal tissues and positively correlates with CTNNB1 expression levels. Key trans-factors that bind to ieCTNNB1 and regulate CTNNB1 transcription were identified. Together, these findings revealed an enhancer-dependent mechanism that controls the dosage of Wnt signaling, hence homeostasis of intestinal epithelia.
2024-10-02 | GSE233978 | GEO
Project description:β-catenin-dependent canonical Wnt signaling plays a plethora of roles in organ development, tissue homeostasis and cancer. Here we identified an upstream enhancer of Ctnnb1 - ieCtnnb1 - that controls intestinal homeostasis. ieCtnnb1 is specifically active in crypts of small and large intestines. Single-cell sequencing revealed that ieCtnnb1 knockout (ieCtnnb1KO) biased epithelial composition and functions of small intestinal crypts – leaning toward absorptive functions at the expense of secretive roles. Deletion of ieCtnnb1 hampered epithelial turnovers in physiologic and regenerative conditions. In contrast, deletion of ieCtnnb1 prevents occurrence and progression of Wnt/β-catenin driving colorectal cancers. The human ieCTNNB1 specifically drives reporter in intestinal crypts and contains a SNP that is associated with CTNNB1 expression levels in human gastrointestinal epithelia. The enhancer activity of ieCTNNB1 in colorectal cancer tissues is higher than that in adjacent normal tissues and positively correlates with CTNNB1 expression levels. Key trans-factors that bind to ieCTNNB1 and regulate CTNNB1 transcription were identified. Together, these findings revealed an enhancer-dependent mechanism that controls the dosage of Wnt signaling, hence homeostasis of intestinal epithelia.
2024-10-02 | GSE233977 | GEO
Project description:Wnt signaling dosage controlled by a Ctnnb1 enhancer balances homeostasis and tumorigenesis of intestinal epithelia
| PRJNA979138 | ENA
Project description:Wnt signaling dosage controlled by a Ctnnb1 enhancer balances homeostasis and tumorigenesis of intestinal epithelia [scRNA-Seq]
| PRJNA979139 | ENA
Project description:Wnt signaling dosage controlled by a Ctnnb1 enhancer balances homeostasis and tumorigenesis of intestinal epithelia [RNA-Seq]
| PRJNA979140 | ENA
Project description:A disintegrin and metalloproteinases (ADAMs) are a family of mSultidomain, membrane-anchored proteases that regulate diverse cellular functions, including cell adhesion, migration, proteolysis and other cell signaling events. Catalytically-active ADAMs act as ectodomain sheddases that proteolytically cleave type I and type II transmembrane proteins and some GPI-anchored proteins from the cellular surface. ADAMs can also modulate other cellular signaling events through a process known as regulated intramembrane proteolysis (RIP). Through their proteolytic activity, ADAMs can rapidly modulate key cell signaling pathways in response to changes in the extracellular environment (e.g. inflammation) and play a central role in coordinating intercellular communication. Dysregulation of these processes through aberrant expression, or sustained ADAM activity, is linked to chronic inflammation, inflammation-associated cancer and tumorigenesis. ADAM10 was the first disintegrin-metalloproteinase demonstrated to have proteolytic activity and is the prototypic ADAM associated with RIP activity (e.g. sequential Notch receptor processing). ADAM10 is abundantly expressed throughout the gastrointestinal tract and during normal intestinal homeostasis ADAM10 regulates many cellular processes associated with intestinal development, cell fate specification and maintenance of intestinal stem cell/progenitor populations. In addition, several signaling pathways that undergo ectodomain shedding by ADAM10 (e.g. Notch, EGFR/ErbB, IL-6/sIL-6R) help control intestinal injury/regenerative responses and may drive intestinal inflammation and colon cancer initiation and progression. Here, I review some of the proposed functions of ADAM10 associated with intestinal crypt homeostasis and tumorigenesis within the gastrointestinal tract in vivo. This article is part of a Special Issue entitled: Proteolysis as a Regulatory Event in Pathophysiology edited by Stefan Rose-John.
| S-EPMC5632589 | biostudies-other
Project description:Afadin interacts with the cytoplasmic region of nectins, which are immunoglobulin-like cell adhesion molecules at adherens junctions, and links them to the actin cytoskeleton. Afadin regulates activities of cells in culture such as directional motility, proliferation and survival. We used Cre-loxP technology to generate mice conditionally lacking afadin specifically in the intestinal epithelia after birth. The loss of afadin caused increased paracellular permeability in the intestinal mucosa and enhanced susceptibility to the tissue destruction induced by dextran sulfate sodium. The junctional architecture of the intestinal epithelia appeared to be preserved, whereas the deficiency of afadin caused the mislocalization of nectin-2 and nectin-3 from adherens junctions to basolateral membrane domains but not that of other components of apical junctions. By contrast, such phenotypic changes were undetected in mice lacking nectin-2, nectin-3 or both. These findings suggest that afadin plays crucial roles, independently of the role as the nectin-afadin module, in barrier function and homeostasis of the intestinal epithelia once the epithelial structure has been established.
| S-EPMC3115770 | biostudies-literature
Project description:Src, originally identified as an oncogene, is a membrane-anchored tyrosine kinase and the Src family kinase (SFK) prototype. SFKs regulate the signalling induced by a wide range of cell surface receptors leading to epithelial cell growth and adhesion. In the intestine, the SFK members Src, Fyn and Yes regulate epithelial cell proliferation and migration during tissue regeneration and transformation, thus implicating conserved and specific functions. In patients with colon cancer, SFK activity is a marker of poor clinical prognosis and a potent driver of metastasis formation. These tumorigenic activities are linked to SFK capacity to promote the dissemination and tumour-initiating capacities of epithelial tumour cells. However, it is unclear how SFKs promote colon tumour formation and metastatic progression because SFK-encoding genes are unfrequently mutated in human cancer. Here, we review recent findings on SFK signalling during intestinal homeostasis, regeneration and tumorigenesis. We also describe the key nongenetic mechanisms underlying SFK tumour activities in colorectal cancer, and discuss how these mechanisms could be exploited in therapeutic strategies to target SFK signalling in metastatic colon cancer.
| S-EPMC7464719 | biostudies-literature
Project description:Deregulation of the Wnt/APC/β-catenin signaling pathway is an important consequence of tumor suppressor APC dysfunction. Genetic and molecular data have established that disruption of this pathway contributes to the development of colorectal cancer. Here, we demonstrate that the transcriptional coregulator RIP140 regulates intestinal homeostasis and tumorigenesis. Using Rip140-null mice and mice overexpressing human RIP140, we found that RIP140 inhibited intestinal epithelial cell proliferation and apoptosis. Interestingly, following whole-body irradiation, mice lacking RIP140 exhibited improved regenerative capacity in the intestine, while mice overexpressing RIP140 displayed reduced recovery. Enhanced RIP140 expression strongly repressed human colon cancer cell proliferation in vitro and after grafting onto nude mice. Moreover, in murine tissues and human cancer cells, RIP140 stimulated APC transcription and inhibited β-catenin activation and target gene expression. Finally, RIP140 mRNA and RIP140 protein levels were decreased in human colon cancers compared with those in normal mucosal tissue, and low levels of RIP140 expression in adenocarcinomas from patients correlated with poor prognosis. Together, these results support a tumor suppressor role for RIP140 in colon cancer.
| S-EPMC4001527 | biostudies-literature
Project description:Vesicular acidification and trafficking are associated with various cellular processes. However, their pathologic relevance to cancer remains elusive. We identified transmembrane protein 9 (TMEM9) as a vesicular acidification regulator. TMEM9 is highly upregulated in colorectal cancer. Proteomic and biochemical analyses show that TMEM9 binds to and facilitates assembly of vacuolar-ATPase (v-ATPase), a vacuolar proton pump, resulting in enhanced vesicular acidification and trafficking. TMEM9-v-ATPase hyperactivates Wnt/?-catenin signalling via lysosomal degradation of adenomatous polyposis coli (APC). Moreover, TMEM9 transactivated by ?-catenin functions as a positive feedback regulator of Wnt signalling in colorectal cancer. Genetic ablation of TMEM9 inhibits colorectal cancer cell proliferation in vitro, ex vivo and in vivo mouse models. Moreover, administration of v-ATPase inhibitors suppresses intestinal tumorigenesis of APC mouse models and human patient-derived xenografts. Our results reveal the unexpected roles of TMEM9-controlled vesicular acidification in hyperactivating Wnt/?-catenin signalling through APC degradation, and propose the blockade of TMEM9-v-ATPase as a viable option for colorectal cancer treatment.
| S-EPMC6261670 | biostudies-literature