Dataset Information

Acidic Bile Salts Induce Epithelial to Mesenchymal Transition via VEGF Signaling in Non-Neoplastic Barrett's Cells.

ABSTRACT: BACKGROUND & AIMS:Metaplastic glands buried under squamous epithelium are frequently detected in patients with Barrett esophagus (BE). This subsquamous intestinal metaplasia might be responsible for cancers that develop despite endoscopic surveillance and for metaplasia recurrences after endoscopic ablation. To determine whether reflux induces BE cells to undergo an epithelial-to-mesenchymal transition (EMT) that produces subsquamous intestinal metaplasia, we assessed EMT in BE cells exposed to acidic bile salts and in rat and human esophageal tissues. METHODS:We compared markers of EMT and cell motility in trans-well and 3-dimensional organotypic culture systems among dysplastic BE epithelial cell lines, nondysplastic telomerase-immortalized BE cell lines (BAR-T), and BAR-T cells exposed acutely or for 20 weeks to acidic bile salts. Vascular endothelial growth factor (VEGF) A was inhibited with a neutralizing antibody or CRISPR-Cas9n and VEGF receptor 2 was inhibited with SU1498 or shRNA, and cells were analyzed by immunohistochemistry, quantitative polymerase chain reaction, or immunoblotting for markers of VEGF signaling and EMT; cell motility was assessed by trans-well assay. We used immunohistochemistry and quantitative polymerase chain reaction to assess EMT markers in the columnar-lined esophagus of rats with surgically induced reflux esophagitis and in esophagectomy specimens from patients with BE. RESULTS:We detected features of EMT (decreased cadherin 1 [CDH1]; increased fibronectin 1, vimentin, and matrix metalloproteinase 2; and increased motility) in dysplastic BE epithelial cell lines and in BAR-T cells exposed for 20 weeks, but not in unexposed BAR-T cells. Acute acidic bile salt exposure induced expression of zinc finger E-box binding homeobox 1 and 2 (ZEB1/2) in BAR-T cells, which decreased their expression of CDH1 and increased motility; inhibitors of VEGF signaling blocked these effects. Columnar-lined esophagus of rats with reflux esophagitis had increased expression of ZEB1/2 and decreased expression of CDH1 compared with controls. Dysplastic BE tissues also had significantly increased levels of ZEB1 and significantly decreased levels of CDH1 compared with nondysplastic BE tissues. CONCLUSIONS:In BE cell lines, acidic bile salts induce EMT by VEGF signaling, which increases expression of ZEB1/2, repressors of CDH1. These observations suggest that reflux induces EMT in metaplastic BE tissues, which promotes development of subsquamous intestinal metaplasia.

SUBMITTER: Zhang Q

PROVIDER: S-EPMC6309503 | biostudies-literature | 2019 Jan

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Acidic Bile Salts Induce Epithelial to Mesenchymal Transition via VEGF Signaling in Non-Neoplastic Barrett's Cells.

Zhang Qiuyang Q Agoston Agoston T AT Pham Thai H TH Zhang Wei W Zhang Xi X Huo Xiaofang X Peng Sui S Bajpai Manisha M Das Kiron K Odze Robert D RD Spechler Stuart J SJ Souza Rhonda F RF

Gastroenterology 20180927 1

<h4>Background & aims</h4>Metaplastic glands buried under squamous epithelium are frequently detected in patients with Barrett esophagus (BE). This subsquamous intestinal metaplasia might be responsible for cancers that develop despite endoscopic surveillance and for metaplasia recurrences after endoscopic ablation. To determine whether reflux induces BE cells to undergo an epithelial-to-mesenchymal transition (EMT) that produces subsquamous intestinal metaplasia, we assessed EMT in BE cells exp ...[more]

PMID: 30268789

Similar Datasets

Project description:The pathogenesis of subsquamous intestinal metaplasia (SSIM), in which glands of Barrett's esophagus (BE) are buried under esophageal squamous epithelium, is unknown. In a rat model of reflux esophagitis, we found that columnar-lined esophagus developed via a wound-healing process involving epithelial-mesenchymal plasticity (EMP) that buried glands under ulcerated squamous epithelium. To explore a role for reflux-induced EMP in BE, we established and characterized human Barrett's organoids and sought evidence of EMP after treatment with acidic bile salts (AB). We optimized media to grow human BE organoids from immortalized human Barrett's cells and from BE biopsies from seven patients, and we characterized histological, morphological, and molecular features of organoid development. Features and markers of EMP were explored following organoid exposure to AB, with and without a collagen I (COL1) matrix to simulate a wound-healing environment. All media successfully initiated organoid growth, but advanced DMEM/F12 (aDMEM) was best at sustaining organoid viability. Using aDMEM, organoids comprising nongoblet and goblet columnar cells that expressed gastric and intestinal cell markers were generated from BE biopsies of all seven patients. After AB treatment, early-stage Barrett's organoids exhibited EMP with loss of membranous E-cadherin and increased protrusive cell migration, events significantly enhanced by COL1. Using human BE biopsies, we have established Barrett's organoids that recapitulate key histological and molecular features of BE to serve as high-fidelity BE models. Our findings suggest that reflux can induce EMP in human BE, potentially enabling Barrett's cells to migrate under adjacent squamous epithelium to form SSIM.NEW & NOTEWORTHY Using Barrett's esophagus (BE) biopsies, we established organoids recapitulating key BE features. During early stages of organoid development, a GERD-like wound environment-induced features of epithelial-mesenchymal plasticity (EMP) in Barrett's progenitor cells, suggesting that reflux-induced EMP can enable Barrett's cells to migrate underneath squamous epithelium to form subsquamous intestinal metaplasia, a condition that may underlie Barrett's cancers that escape detection by endoscopic surveillance, and recurrences of Barrett's metaplasia following endoscopic eradication therapy.

Project description:The frequency of esophageal adenocarcinoma is rising despite widespread use of proton pump inhibitors (PPIs), which heal reflux esophagitis but do not prevent reflux of weakly acidic gastric juice and bile in Barrett's esophagus patients. We aimed to determine if weakly acidic (pH 5.5) bile salt medium (WABM) causes DNA damage in Barrett's cells. Because p53 is inactivated frequently in Barrett's esophagus and p38 can assume p53 functions, we explored p38's role in DNA damage response and repair. We exposed Barrett's cells with or without p53 knockdown to WABM, and evaluated DNA damage, its response and repair, and whether these effects are p38 dependent. We also measured phospho-p38 in biopsies of Barrett's metaplasia exposed to deoxycholic acid (DCA). WABM caused phospho-H2AX increases that were blocked by a reactive oxygen species (ROS) scavenger. WABM increased phospho-p38 and reduced bromodeoxyuridine incorporation (an index of S phase entry). Repair of WABM-induced DNA damage proceeded through p38-mediated base excision repair (BER) associated with reduction-oxidation factor 1-apurinic/apyrimidinic endonuclease I (Ref-1/APE1). Cells treated with WABM supplemented with ursodeoxycholic acid (UDCA) exhibited enhanced p38-mediated responses to DNA damage. All of these effects were observed in p53-intact and p53-deficient Barrett's cells. In patients, esophageal DCA perfusion significantly increased phospho-p38 in Barrett's metaplasia. WABM exposure generates ROS, causing oxidative DNA damage in Barrett's cells, a mechanism possibly underlying the rising frequency of esophageal adenocarcinoma despite PPI usage. p38 plays a central role in oxidative DNA damage response and Ref-1/APE1-associated BER, suggesting potential chemopreventive roles for agents like UDCA that increase p38 activity in Barrett's esophagus.NEW & NOTEWORTHY We found that weakly acidic bile salt solutions, with compositions similar to the refluxed gastric juice of gastroesophageal reflux disease patients on proton pump inhibitors, cause oxidative DNA damage in Barrett's metaplasia that could contribute to the development of esophageal adenocarcinoma. We also have elucidated a critical role for p38 in Barrett's metaplasia in its response to and repair of oxidative DNA damage, suggesting a potential chemopreventive role for agents like ursodeoxycholic acid that increase p38 activity in Barrett's esophagus.

Dataset Information

Acidic Bile Salts Induce Epithelial to Mesenchymal Transition via VEGF Signaling in Non-Neoplastic Barrett's Cells.

Publications

Acidic Bile Salts Induce Epithelial to Mesenchymal Transition via VEGF Signaling in Non-Neoplastic Barrett's Cells.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets