DICKKOPF-1 locates in the nucleus of human differentiated epithelial intestinal and mammary cells and regulates gene expression
Ontology highlight
ABSTRACT:
ORGANISM(S): Homo sapiens
SUBMITTER: beatriz Morte
PROVIDER: E-GEOD-35272 | biostudies-arrayexpress |
REPOSITORIES: biostudies-arrayexpress
Similar Datasets
Project description:Wnt/b-catenin pathway is a key modulator of intestinal homeostasis by regulating stem cell biology during gut organogenesis and in adult life. DICKKOPF (DKK)-1 is a secreted inhibitor of Wnt/b-catenin signaling from plasma membrane receptors. We found that in human intestine, DKK-1 locates within the nucleus of differentiated enterocytes and enteroendocrine cells but not of proliferating and stem cells at the bottom of the crypts. DKK-1 is also nuclear in colon cancer cells locating at sites of active gene transcription. ChIP-seq and transcriptomic analysis both confirmed that DKK-1 binds chromatin and regulates gene expression. Thus, we demonstrate that DKK-1 is a multifunctional protein that inhibits Wnt/b-catenin signaling at plasma membrane and controls specific genes in the nucleus, suggesting that these functions are relevant for intestinal homeostasis.
2015-03-30 | GSE35272 | GEO
Project description:Sporadic colorectal cancer (CRC) insurgence and progression depend on the activation of Wnt/?-catenin signaling. Dickkopf (DKK)-1 is an extracellular inhibitor of Wnt/?-catenin signaling that also has undefined ?-catenin-independent actions. Here we report for the first time that a proportion of DKK-1 locates within the nucleus of healthy small intestine and colon mucosa, and of CRC cells at specific chromatin sites of active transcription. Moreover, we show that DKK-1 regulates several cancer-related genes including the cancer stem cell marker aldehyde dehydrogenase 1A1 (ALDH1A1) and Ral-binding protein 1-associated Eps domain-containing 2 (REPS2), which are involved in detoxification of chemotherapeutic agents. Nuclear DKK-1 expression is lost along CRC progression; however, it remains high in a subset (15%) of CRC patients (n = 699) and associates with decreased progression-free survival (PFS) after chemotherapy administration and overall survival (OS) [adjusted HR, 1.65; 95% confidence interval (CI), 1.23-2.21; P = 0.002)]. Overexpression of ALDH1A1 and REPS2 associates with nuclear DKK-1 expression in tumors and correlates with decreased OS (P = 0.001 and 0.014) and PFS. In summary, our findings demonstrate a novel location of DKK-1 within the cell nucleus and support a role of nuclear DKK-1 as a predictive biomarker of chemoresistance in colorectal cancer. Analysis of DKK-1 location and associated roles in human colon cancer cells and crypts of small and large bowel.
2015-05-13 | E-GEOD-31170 | biostudies-arrayexpress
Project description:Sporadic colorectal cancer (CRC) insurgence and progression depend on the activation of Wnt/β-catenin signaling. Dickkopf (DKK)-1 is an extracellular inhibitor of Wnt/β-catenin signaling that also has undefined β-catenin-independent actions. Here we report for the first time that a proportion of DKK-1 locates within the nucleus of healthy small intestine and colon mucosa, and of CRC cells at specific chromatin sites of active transcription. Moreover, we show that DKK-1 regulates several cancer-related genes including the cancer stem cell marker aldehyde dehydrogenase 1A1 (ALDH1A1) and Ral-binding protein 1-associated Eps domain-containing 2 (REPS2), which are involved in detoxification of chemotherapeutic agents. Nuclear DKK-1 expression is lost along CRC progression; however, it remains high in a subset (15%) of CRC patients (n = 699) and associates with decreased progression-free survival (PFS) after chemotherapy administration and overall survival (OS) [adjusted HR, 1.65; 95% confidence interval (CI), 1.23-2.21; P = 0.002)]. Overexpression of ALDH1A1 and REPS2 associates with nuclear DKK-1 expression in tumors and correlates with decreased OS (P = 0.001 and 0.014) and PFS. In summary, our findings demonstrate a novel location of DKK-1 within the cell nucleus and support a role of nuclear DKK-1 as a predictive biomarker of chemoresistance in colorectal cancer.
2015-05-13 | GSE31170 | GEO
Project description:The Wnt signaling pathway is deregulated in over 90% of human colorectal cancers. β Catenin, the central signal transducer of the Wnt pathway, can directly modulate gene expression by interacting with transcription factors of the TCF/LEF-family. In the present study we investigate the role of Wnt signaling in the homeostasis of intestinal epithelium using tissue-specific, inducible beta-catenin gene ablation in adult mice. Block of Wnt/beta-catenin signaling resulted in rapid loss of transient-amplifying cells and crypt structures. Importantly, intestinal stem cells were induced to terminally differentiate upon deletion of beta-catenin resulting in a complete block of intestinal homeostasis and fatal loss of intestinal function. Transcriptional profiling of mutant crypt mRNA isolated by laser capture micro dissection confirmed those observations and allowed to identify genes potentially responsible for the functional preservation of intestinal stem cells. Experiment Overall Design: laser capture microdissection of intestinal crypts, control vs. beta-catenin mutant (2days after induction of deletion by tamoxifen), two rounds of amplification of mRNA
2008-06-16 | E-GEOD-8818 | biostudies-arrayexpress
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: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:Background: Wnt signaling maintains the undifferentiated state of intestinal crypt progenitor cells by inducing the formation of nuclear TCF4/beta-catenin complexes. In colorectal cancer, activating mutations in Wnt pathway components cause inappropriate activation of TCF4/beta-catenin -driven transcription. Despite the passage of a decade after the discovery of TCF4 and beta-catenin as the molecular effectors of the Wnt signal, few transcriptional activators essential and unique to the regulation of this transcription program have been found. Methodology/Principal Findings: Using proteomics, we identified the leukemia-associated Mllt10/Af10 and the methyltransferase Dot1l, as Tcf4/beta-catenin interactors in mouse small intestinal crypts. Mllt10/Af10-Dot1l, essential for transcription elongation, are recruited to Wnt target genes in a beta-catenin -dependent manner, resulting in H3K79 methylation over their coding regions in vivo in proliferative crypts of mouse small intestine, in colorectal cancer and Wnt-inducible HEK293T cells. Depletion of MLLT10/AF10 in colorectal cancer and Wnt-inducible HEK293T cells followed by expression array analysis identifies MLLT10/AF10 and DOT1L as essential activators dedicated to Wnt target gene regulation. In contrast, previously published b-catenin coactivators p300 and beta-catenin displayed a more pleiotropic target gene expression profile controlling Wnt and other pathways. tcf4, mllt10/af10 and dot1l are co-expressed in Wnt-driven tissues in zebrafish and essential for Wnt-reporter activity. Intestinal differentiation defects in apc-mutant zebrafish can be rescued by depletion of Mllt10 and Dot1l, establishing these genes as activators downstream of Apc in Wnt target gene activation in vivo. Morpholino-depletion of mllt10/af10-dot1l in zebrafish results in defects in intestinal homeostasis and a significant reduction in the in vivo expression of direct Wnt target genes and in the number of proliferative intestinal epithelial cells. Conclusions/Significance: We conclude that Mllt10/Af10-Dot1l are essential, dedicated activators of Wnt-dependent transcription, critical for maintenance of intestinal proliferation and homeostasis. The methyltransferase Dot1l may present an attractive candidate for drug targeting in colorectal cancer. 6 samples for Ls174T cells: si-b-catenin against si-control and dyeswap of it, si-control, si-MLLT10, si-BRG1 and si-P300 are hybridized against common reference RNA; 6 samples of HEK293T cells: Wnt3A or control medium (CM) induction for 9 hours, si-MLLT10, si-DOT1L, si-BRG1 and si-P300 upon 9 hour Wnt3A induction are all hybridized against common reference RNA
2010-04-20 | E-GEOD-21367 | biostudies-arrayexpress
Project description:Although the role of the Wnt pathway in colon carcinogenesis has been described previously, it has been recently demonstrated that Wnt signaling originates from highly dynamic nano-assemblies at the plasma membrane. However, little is known regarding the role of oncogenic APC in reshaping Wnt nanodomains. This is noteworthy, because oncogenic APC does not act autonomously and requires activation of Wnt effectors upstream of APC to drive aberrant Wnt signaling. Here, we demonstrate the role of oncogenic APC in increasing plasma membrane free cholesterol and rigidity, thereby modulating Wnt signaling hubs. This results in an overactivation of Wnt signaling in the colon. Finally, using the Drosophila sterol auxotroph model, we demonstrate the unique ability of exogenous free cholesterol to disrupt plasma membrane homeostasis and drive Wnt signaling in a wildtype APC background. Collectively, these findings provide a mechanistic link between oncogenic APC, loss of plasma membrane homeostasis and CRC development.
2023-06-21 | GSE234522 | GEO
Project description:Background: Wnt signaling maintains the undifferentiated state of intestinal crypt progenitor cells by inducing the formation of nuclear TCF4/beta-catenin complexes. In colorectal cancer, activating mutations in Wnt pathway components cause inappropriate activation of TCF4/beta-catenin-driven transcription. Despite the passage of a decade after the discovery of TCF4 and beta-catenin as the molecular effectors of the Wnt signal, few transcriptional activators essential and unique to the regulation of this transcription program have been found. Methodology/Principal Findings: Using proteomics, we identified the leukemia-associated Mllt10/Af10 and the methyltransferase Dot1l, as Tcf4/beta-catenin interactors in mouse small intestinal crypts. Mllt10/Af10-Dot1l, essential for transcription elongation, are recruited to Wnt target genes in a beta-catenin -dependent manner, resulting in H3K79 methylation over their coding regions in vivo in proliferative crypts of mouse small intestine, in colorectal cancer and Wnt-inducible HEK293T cells. Depletion of MLLT10/AF10 in colorectal cancer and Wnt-inducible HEK293T cells followed by expression array analysis identifies MLLT10/AF10 and DOT1L as essential activators dedicated to Wnt target gene regulation. In contrast, previously published b-catenin coactivators p300 and beta-catenin displayed a more pleiotropic target gene expression profile controlling Wnt and other pathways. tcf4, mllt10/af10 and dot1l are co-expressed in Wnt-driven tissues in zebrafish and essential for Wnt-reporter activity. Intestinal differentiation defects in apc-mutant zebrafish can be rescued by depletion of Mllt10 and Dot1l, establishing these genes as activators downstream of Apc in Wnt target gene activation in vivo. Morpholino-depletion of mllt10/af10-dot1l in zebrafish results in defects in intestinal homeostasis and a significant reduction in the in vivo expression of direct Wnt target genes and in the number of proliferative intestinal epithelial cells. Conclusions/Significance: We conclude that Mllt10/Af10-Dot1l are essential, dedicated activators of Wnt-dependent transcription, critical for maintenance of intestinal proliferation and homeostasis. The methyltransferase Dot1l may present an attractive candidate for drug targeting in colorectal cancer.
2010-04-20 | GSE21367 | GEO
Project description:The homeostasis of the gut epithelium relies upon continuous renewal and proliferation of crypt-resident intestinal epithelial stem cells (IESCs). Wnt/β-catenin signaling is required for IESC maintenance, however, it remains unclear how this pathway selectively governs the identity and proliferative decisions of IESCs. Here, we demonstrate that C-terminally-recruited transcriptional co-factors of β-catenin act as all-or-nothing regulators of Wnt-target gene expression. Blocking their interactions with β-catenin rapidly induces loss of IESCs and intestinal homeostasis. Conversely, N-terminally recruited co-factors fine-tune β-catenin’s transcriptional output to ensure proper self-renewal and proliferative behaviour of IESCs. Impairment of N-terminal interactions triggers transient hyperproliferation of IESCs, resulting in exhaustion of the self-renewing stem cell pool. IESC mis-differentiation, accompanied by intrinsic and extrinsic stress signalling results in a process resembling aberrant "villisation" of intestinal crypts. Our data suggest that IESC-specific Wnt/β-catenin output requires discrete regulation of transcription by transcriptional co-factors.
2020-04-21 | GSE148942 | GEO