Other search tools

About this data

The publication data currently available has been vetted by Vanderbilt faculty, staff, administrators and trainees. The data itself is retrieved directly from NCBI's PubMed and is automatically updated on a weekly basis to ensure accuracy and completeness.

If you have any questions or comments, please contact us.

Results: 1 to 10 of 33

Publication Record

Connections

APC Inhibits Ligand-Independent Wnt Signaling by the Clathrin Endocytic Pathway.
Saito-Diaz K, Benchabane H, Tiwari A, Tian A, Li B, Thompson JJ, Hyde AS, Sawyer LM, Jodoin JN, Santos E, Lee LA, Coffey RJ, Beauchamp RD, Williams CS, Kenworthy AK, Robbins DJ, Ahmed Y, Lee E
(2018) Dev Cell 44: 566-581.e8
MeSH Terms: Adenomatous Polyposis Coli Protein, Animals, Cells, Cultured, Clathrin, Drosophila melanogaster, Endocytosis, Female, Humans, Infant, Ligands, Male, Mice, Mice, Inbred C57BL, Mice, Knockout, Middle Aged, Wnt Proteins, Wnt Signaling Pathway, beta Catenin
Show Abstract · Added March 14, 2018
Adenomatous polyposis coli (APC) mutations cause Wnt pathway activation in human cancers. Current models for APC action emphasize its role in promoting β-catenin degradation downstream of Wnt receptors. Unexpectedly, we find that blocking Wnt receptor activity in APC-deficient cells inhibits Wnt signaling independently of Wnt ligand. We also show that inducible loss of APC is rapidly followed by Wnt receptor activation and increased β-catenin levels. In contrast, APC2 loss does not promote receptor activation. We show that APC exists in a complex with clathrin and that Wnt pathway activation in APC-deficient cells requires clathrin-mediated endocytosis. Finally, we demonstrate conservation of this mechanism in Drosophila intestinal stem cells. We propose a model in which APC and APC2 function to promote β-catenin degradation, and APC also acts as a molecular "gatekeeper" to block receptor activation via the clathrin pathway.
Copyright © 2018 Elsevier Inc. All rights reserved.
0 Communities
4 Members
0 Resources
18 MeSH Terms
Patients with familial adenomatous polyposis harbor colonic biofilms containing tumorigenic bacteria.
Dejea CM, Fathi P, Craig JM, Boleij A, Taddese R, Geis AL, Wu X, DeStefano Shields CE, Hechenbleikner EM, Huso DL, Anders RA, Giardiello FM, Wick EC, Wang H, Wu S, Pardoll DM, Housseau F, Sears CL
(2018) Science 359: 592-597
MeSH Terms: Adenomatous Polyposis Coli, Animals, Bacterial Toxins, Bacteroides fragilis, Biofilms, Carcinogenesis, Colon, Colonic Neoplasms, DNA Damage, Escherichia coli, Gastrointestinal Microbiome, Humans, Interleukin-17, Intestinal Mucosa, Metalloendopeptidases, Mice, Peptides, Polyketides, Precancerous Conditions
Show Abstract · Added March 20, 2018
Individuals with sporadic colorectal cancer (CRC) frequently harbor abnormalities in the composition of the gut microbiome; however, the microbiota associated with precancerous lesions in hereditary CRC remains largely unknown. We studied colonic mucosa of patients with familial adenomatous polyposis (FAP), who develop benign precursor lesions (polyps) early in life. We identified patchy bacterial biofilms composed predominately of and Genes for colibactin () and toxin (), encoding secreted oncotoxins, were highly enriched in FAP patients' colonic mucosa compared to healthy individuals. Tumor-prone mice cocolonized with (expressing colibactin), and enterotoxigenic showed increased interleukin-17 in the colon and DNA damage in colonic epithelium with faster tumor onset and greater mortality, compared to mice with either bacterial strain alone. These data suggest an unexpected link between early neoplasia of the colon and tumorigenic bacteria.
Copyright © 2018 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.
0 Communities
1 Members
0 Resources
19 MeSH Terms
Bacteroides fragilis Toxin Coordinates a Pro-carcinogenic Inflammatory Cascade via Targeting of Colonic Epithelial Cells.
Chung L, Thiele Orberg E, Geis AL, Chan JL, Fu K, DeStefano Shields CE, Dejea CM, Fathi P, Chen J, Finard BB, Tam AJ, McAllister F, Fan H, Wu X, Ganguly S, Lebid A, Metz P, Van Meerbeke SW, Huso DL, Wick EC, Pardoll DM, Wan F, Wu S, Sears CL, Housseau F
(2018) Cell Host Microbe 23: 203-214.e5
MeSH Terms: Adenomatous Polyposis Coli Protein, Animals, Bacterial Toxins, Bacteroides fragilis, Carcinogenesis, Cell Line, Tumor, Colon, Colorectal Neoplasms, Enzyme Activation, Epithelial Cells, Female, Gene Deletion, HT29 Cells, Humans, Inflammation, Interleukin-17, Male, Metalloendopeptidases, Mice, Mice, Inbred C57BL, Mice, Knockout, Myeloid Cells, Receptors, Interleukin-17, Receptors, Interleukin-8B, STAT3 Transcription Factor, Transcription Factor RelA
Show Abstract · Added March 20, 2018
Pro-carcinogenic bacteria have the potential to initiate and/or promote colon cancer, in part via immune mechanisms that are incompletely understood. Using Apc mice colonized with the human pathobiont enterotoxigenic Bacteroides fragilis (ETBF) as a model of microbe-induced colon tumorigenesis, we show that the Bacteroides fragilis toxin (BFT) triggers a pro-carcinogenic, multi-step inflammatory cascade requiring IL-17R, NF-κB, and Stat3 signaling in colonic epithelial cells (CECs). Although necessary, Stat3 activation in CECs is not sufficient to trigger ETBF colon tumorigenesis. Notably, IL-17-dependent NF-κB activation in CECs induces a proximal to distal mucosal gradient of C-X-C chemokines, including CXCL1, that mediates the recruitment of CXCR2-expressing polymorphonuclear immature myeloid cells with parallel onset of ETBF-mediated distal colon tumorigenesis. Thus, BFT induces a pro-carcinogenic signaling relay from the CEC to a mucosal Th17 response that results in selective NF-κB activation in distal colon CECs, which collectively triggers myeloid-cell-dependent distal colon tumorigenesis.
Copyright © 2018 Elsevier Inc. All rights reserved.
0 Communities
1 Members
0 Resources
26 MeSH Terms
p120-Catenin is an obligate haploinsufficient tumor suppressor in intestinal neoplasia.
Short SP, Kondo J, Smalley-Freed WG, Takeda H, Dohn MR, Powell AE, Carnahan RH, Washington MK, Tripathi M, Payne DM, Jenkins NA, Copeland NG, Coffey RJ, Reynolds AB
(2017) J Clin Invest 127: 4462-4476
MeSH Terms: Adenomatous Polyposis Coli Protein, Animals, Catenins, Haploinsufficiency, Intestinal Neoplasms, Mice, Mice, Knockout, rho-Associated Kinases
Show Abstract · Added March 14, 2018
p120-Catenin (p120) functions as a tumor suppressor in intestinal cancer, but the mechanism is unclear. Here, using conditional p120 knockout in Apc-sensitized mouse models of intestinal cancer, we have identified p120 as an "obligatory" haploinsufficient tumor suppressor. Whereas monoallelic loss of p120 was associated with a significant increase in tumor multiplicity, loss of both alleles was never observed in tumors from these mice. Moreover, forced ablation of the second allele did not further enhance tumorigenesis, but instead induced synthetic lethality in combination with Apc loss of heterozygosity. In tumor-derived organoid cultures, elimination of both p120 alleles resulted in caspase-3-dependent apoptosis that was blocked by inhibition of Rho kinase (ROCK). With ROCK inhibition, however, p120-ablated organoids exhibited a branching phenotype and a substantial increase in cell proliferation. Access to data from Sleeping Beauty mutagenesis screens afforded an opportunity to directly assess the tumorigenic impact of p120 haploinsufficiency relative to other candidate drivers. Remarkably, p120 ranked third among the 919 drivers identified. Cofactors α-catenin and epithelial cadherin (E-cadherin) were also among the highest scoring candidates, indicating a mechanism at the level of the intact complex that may play an important role at very early stages of of intestinal tumorigenesis while simultaneously restricting outright loss via synthetic lethality.
0 Communities
2 Members
0 Resources
8 MeSH Terms
Wnt/Wingless Pathway Activation Is Promoted by a Critical Threshold of Axin Maintained by the Tumor Suppressor APC and the ADP-Ribose Polymerase Tankyrase.
Wang Z, Tacchelly-Benites O, Yang E, Thorne CA, Nojima H, Lee E, Ahmed Y
(2016) Genetics 203: 269-81
MeSH Terms: Adenomatous Polyposis Coli Protein, Animals, Axin Protein, Drosophila, Genotype, Mitosis, Protein Interaction Domains and Motifs, Protein Stability, Tankyrases, Wnt Proteins, Wnt Signaling Pathway, Xenopus
Show Abstract · Added February 13, 2017
Wnt/β-catenin signal transduction directs metazoan development and is deregulated in numerous human congenital disorders and cancers. In the absence of Wnt stimulation, a multiprotein "destruction complex," assembled by the scaffold protein Axin, targets the key transcriptional activator β-catenin for proteolysis. Axin is maintained at very low levels that limit destruction complex activity, a property that is currently being exploited in the development of novel therapeutics for Wnt-driven cancers. Here, we use an in vivo approach in Drosophila to determine how tightly basal Axin levels must be controlled for Wnt/Wingless pathway activation, and how Axin stability is regulated. We find that for nearly all Wingless-driven developmental processes, a three- to fourfold increase in Axin is insufficient to inhibit signaling, setting a lower-limit for the threshold level of Axin in the majority of in vivo contexts. Further, we find that both the tumor suppressor adenomatous polyposis coli (APC) and the ADP-ribose polymerase Tankyrase (Tnks) have evolutionarily conserved roles in maintaining basal Axin levels below this in vivo threshold, and we define separable domains in Axin that are important for APC- or Tnks-dependent destabilization. Together, these findings reveal that both APC and Tnks maintain basal Axin levels below a critical in vivo threshold to promote robust pathway activation following Wnt stimulation.
Copyright © 2016 by the Genetics Society of America.
0 Communities
1 Members
0 Resources
12 MeSH Terms
Activation of Wnt/β-catenin signaling in a subpopulation of murine prostate luminal epithelial cells induces high grade prostate intraepithelial neoplasia.
Valkenburg KC, Yu X, De Marzo AM, Spiering TJ, Matusik RJ, Williams BO
(2014) Prostate 74: 1506-20
MeSH Terms: Adenomatous Polyposis Coli Protein, Animals, Castration, Enzyme-Linked Immunosorbent Assay, Epithelial Cells, Immunohistochemistry, Male, Mice, Prostate, Prostatic Intraepithelial Neoplasia, Prostatic Neoplasms, Reverse Transcriptase Polymerase Chain Reaction, Tamoxifen, Wnt Proteins, Wnt Signaling Pathway, beta Catenin
Show Abstract · Added January 20, 2015
BACKGROUND - Wnt/β-catenin signaling is important for prostate development and cancer in humans. Activation of this pathway in differentiated luminal cells of mice induces high-grade prostate intraepithelial neoplasia (HGPIN). Though the cell of origin of prostate cancer has yet to be conclusively identified, a castration-resistant Nkx3.1-expressing cell (CARN) may act as a cell of origin for prostate cancer.
METHODS - To activate Wnt/β-catenin signaling in CARNs, we crossed mice carrying tamoxifen-inducible Nkx3.1-driven Cre to mice containing loxP sites in order to either conditionally knock out adenomatous polyposis coli (Apc) or constitutively activate β-catenin directly. We then castrated and hormonally regenerated these mice to target the CARN population.
RESULTS - Loss of Apc in hormonally normal mice induced HGPIN; however, after one or more rounds of castration and hormonal regeneration, Apc-null CARNs disappeared. Alternatively, when β-catenin was constitutively activated under the same conditions, HGPIN was apparent.
CONCLUSION - Activation of Wnt/β-catenin signaling via Apc deletion is sufficient to produce HGPIN in hormonally normal mice. Loss of Apc may destabilize the CARN population under regeneration conditions. When β-catenin is constitutively activated, HGPIN occurs in hormonally regenerated mice. A second genetic hit is likely required to cause progression to carcinoma and metastasis.
© 2014 Wiley Periodicals, Inc.
1 Communities
1 Members
0 Resources
16 MeSH Terms
Repurposing the FDA-approved pinworm drug pyrvinium as a novel chemotherapeutic agent for intestinal polyposis.
Li B, Flaveny CA, Giambelli C, Fei DL, Han L, Hang BI, Bai F, Pei XH, Nose V, Burlingame O, Capobianco AJ, Orton D, Lee E, Robbins DJ
(2014) PLoS One 9: e101969
MeSH Terms: Adenomatous Polyposis Coli, Animals, Antineoplastic Agents, Cell Survival, Drug Approval, Drug Repositioning, Drug Screening Assays, Antitumor, HCT116 Cells, Humans, Mice, Inbred C57BL, Mice, Transgenic, Pyrvinium Compounds, Wnt Signaling Pathway
Show Abstract · Added November 2, 2015
Mutations in the WNT-pathway regulator ADENOMATOUS POLYPOSIS COLI (APC) promote aberrant activation of the WNT pathway that is responsible for APC-associated diseases such as Familial Adenomatous Polyposis (FAP) and 85% of spontaneous colorectal cancers (CRC). FAP is characterized by multiple intestinal adenomas, which inexorably result in CRC. Surprisingly, given their common occurrence, there are few effective chemotherapeutic drugs for FAP. Here we show that the FDA-approved, anti-helminthic drug Pyrvinium attenuates the growth of WNT-dependent CRC cells and does so via activation of CK1α. Furthermore, we show that Pyrvinium can function as an in vivo inhibitor of WNT-signaling and polyposis in a mouse model of FAP: APCmin mice. Oral administration of Pyrvinium, a CK1α agonist, attenuated the levels of WNT-driven biomarkers and inhibited adenoma formation in APCmin mice. Considering its well-documented safe use for treating enterobiasis in humans, our findings suggest that Pyrvinium could be repurposed for the clinical treatment of APC-associated polyposes.
0 Communities
1 Members
0 Resources
13 MeSH Terms
Claudin-1 overexpression in intestinal epithelial cells enhances susceptibility to adenamatous polyposis coli-mediated colon tumorigenesis.
Pope JL, Ahmad R, Bhat AA, Washington MK, Singh AB, Dhawan P
(2014) Mol Cancer 13: 167
MeSH Terms: Adenomatous Polyposis Coli, Adenomatous Polyposis Coli Protein, Animals, Cell Transformation, Neoplastic, Claudin-1, Colonic Neoplasms, Epithelial Cells, Gene Expression Regulation, Neoplastic, Interleukin-23 Subunit p19, Intestinal Mucosa, Intestines, Mice, Mucin-2
Show Abstract · Added December 8, 2014
BACKGROUND - The tight junction protein Claudin-1, a claudin family member, has been implicated in several gastro-intestinal pathologies including inflammatory bowel disease (IBD) and colorectal cancer (CRC). In this regard, we have demonstrated that claudin-1 expression in colon cancer cells potentiates their tumorigenic ability while in vivo expression of claudin-1 in the intestinal epithelial cells (IECs) promotes Notch-activation, inhibits goblet cell differentiation and renders susceptibility to mucosal inflammation. Notably, a key role of inflammation in colon cancer progression is being appreciated. Therefore, we examined whether inflammation plays an important role in claudin-1-dependent upregulation of colon carcinogenesis.
METHODS - APCmin mice were crossed with Villin-claudin-1 transgenic mice to generate APC-Cldn1 mice. H&E stained colon tissues were assessed for tumor number, size and histological grade. Additionally, microarray and qPCR analyses of colonic tumors were performed to assess molecular changes due to claudin-1 expression. APC-Cldn1 and APCmin controls were assessed for colonic permeability via rectal administration of FITC-dextran, and bacterial translocation via qPCR analysis of 16S rDNA.
RESULTS - Claudin-1 overexpression in APCmin mice significantly increased (~4-fold) colonic tumor growth and size, and decreased survival. Furthermore, transcriptome analysis supported upregulated proliferation, and increased Wnt and Notch-signaling in APC-Cldn1 mice. APC-Cldn1 mice also demonstrated inhibition of mucosal defense genes while expression of pro-inflammatory genes was sharply upregulated, especially the IL-23/IL-17 signaling. We predict that increased Notch/Wnt-signaling underlie the early onset of adenoma formation in APC-Cldn1 mice. An increase in mucosal permeability due to the adenomas and the inherent barrier defect in these mice further facilitate bacterial translocation into the mucosa to induce inflammation, which in turn promote the tumorigenesis.
CONCLUSION - Taken together, these results confirm the role of claudin-1 as a promoter of colon tumorigenesis and further identify the role of the dysregulated antigen-tumor interaction and inflammation in claudin-1-dependent upregulation of colon tumorigenesis.
1 Communities
1 Members
0 Resources
13 MeSH Terms
Inducible loss of one Apc allele in Lrig1-expressing progenitor cells results in multiple distal colonic tumors with features of familial adenomatous polyposis.
Powell AE, Vlacich G, Zhao ZY, McKinley ET, Washington MK, Manning HC, Coffey RJ
(2014) Am J Physiol Gastrointest Liver Physiol 307: G16-23
MeSH Terms: Adenomatous Polyposis Coli, Animals, Cell Transformation, Neoplastic, Colon, Colonoscopy, Disease Models, Animal, Genes, APC, Hypertrophy, Membrane Glycoproteins, Mice, Mice, Transgenic, Neoplastic Stem Cells, Nerve Tissue Proteins, Positron-Emission Tomography, Precancerous Conditions, Retinal Pigment Epithelium, Time Factors
Show Abstract · Added May 20, 2014
Individuals with familial adenomatous polyposis (FAP) harbor a germline mutation in adenomatous polyposis coli (APC). The major clinical manifestation is development of multiple colonic tumors at a young age due to stochastic loss of the remaining APC allele. Extracolonic features, including periampullary tumors, gastric abnormalities, and congenital hypertrophy of the retinal pigment epithelium, may occur. The objective of this study was to develop a mouse model that simulates these features of FAP. We combined our Lrig1-CreERT2/+ mice with Apcfl/+ mice, eliminated one copy of Apc in leucine-rich repeats and immunoglobulin-like domains protein 1 (Lrig1)-positive (Lrig1(+)) progenitor cells with tamoxifen injection, and monitored tumor formation in the colon by colonoscopy and PET. Initial loss of one Apc allele in Lrig1(+) cells results in a predictable pattern of preneoplastic changes, culminating in multiple distal colonic tumors within 50 days of induction, as well as the extracolonic manifestations of FAP mentioned above. We show that tumor formation can be monitored by noninvasive PET imaging. This inducible stem cell-driven model recapitulates features of FAP and offers a tractable platform on which therapeutic interventions can be monitored over time by colonoscopy and noninvasive imaging.
Copyright © 2014 the American Physiological Society.
1 Communities
4 Members
0 Resources
17 MeSH Terms
The RNA-binding protein Fus directs translation of localized mRNAs in APC-RNP granules.
Yasuda K, Zhang H, Loiselle D, Haystead T, Macara IG, Mili S
(2013) J Cell Biol 203: 737-46
MeSH Terms: Adenomatous Polyposis Coli Protein, Animals, Cytoplasmic Granules, Mice, NIH 3T3 Cells, Protein Biosynthesis, RNA, Messenger, RNA-Binding Protein FUS, Ribonucleoproteins
Show Abstract · Added March 20, 2014
RNA localization pathways direct numerous mRNAs to distinct subcellular regions and affect many physiological processes. In one such pathway the tumor-suppressor protein adenomatous polyposis coli (APC) targets RNAs to cell protrusions, forming APC-containing ribonucleoprotein complexes (APC-RNPs). Here, we show that APC-RNPs associate with the RNA-binding protein Fus/TLS (fused in sarcoma/translocated in liposarcoma). Fus is not required for APC-RNP localization but is required for efficient translation of associated transcripts. Labeling of newly synthesized proteins revealed that Fus promotes translation preferentially within protrusions. Mutations in Fus cause amyotrophic lateral sclerosis (ALS) and the mutant protein forms inclusions that appear to correspond to stress granules. We show that overexpression or mutation of Fus results in formation of granules, which preferentially recruit APC-RNPs. Remarkably, these granules are not translationally silent. Instead, APC-RNP transcripts are translated within cytoplasmic Fus granules. These results unexpectedly show that translation can occur within stress-like granules. Importantly, they identify a new local function for cytoplasmic Fus with implications for ALS pathology.
0 Communities
1 Members
0 Resources
9 MeSH Terms