Project description:Background & Aims: Tissue metaplasia is uncommon in adults because established cis-element programs resist rewiring. In Barrett’s esophagus, the distal esophageal mucosa acquires predominantly intestinal character, with notable gastric features, and is predisposed to develop invasive cancers. We sought to understand the chromatin underpinnings of Barrett’s metaplasia and why it commonly displays simultaneous gastric and intestinal properties. Methods: We profiled cis-regulatory elements with active histone modifications in primary human biopsy materials using chromatin immunoprecipitation followed by DNA sequencing (ChIP-seq). Mutations in Barrett’s esophagus were examined in relation to tissue-specific enhancer landscapes using a random-forest machine learning algorithm. We also profiled open chromatin at single-cell resolution in primary Barrett’s biopsy specimens using the assay for transposase-accessible chromatin (ATAC-seq). We used one- and two-color immunohistochemistry to examine protein expression of tissue-restricted genes. Results: Barrett’s esophagus bears epigenome fingerprints of human stomach and intestinal columnar, but not esophageal squamous, epithelia. Mutational patterns were best explained as arising on the epigenome background of active gastric cis-elements, supporting the view that adjoining stomach epithelium is a likely tissue source. Individual cells in Barrett’s metaplasia co-express gastric and intestinal genes, reflecting concomitant chromatin access at enhancers ordinarily restricted to one or the other epithelium. Protein expression of stomach-specific mucins, CLDN18, and a novel gastric marker, ANXA10, revealed extensive tissue and sub-clonal heterogeneity of dual stomach-intestinal cell states. Conclusions: These findings reveal mixed and dynamic tissue-restricted chromatin states and phenotypic heterogeneity in Barrett’s esophagus. Pervasive intra-gland variation argues against stem-cell governance of this phenotype.
Project description:Esophageal adenocarcinoma (EAC) has the fastest increase of any cancer in the US and Europe, and arises in the setting of Barrett’s esophagus (BE), defined by replacement of normal squamous epithelium with columnar intestinal-like epithelium. BE is thought to result from chronic esophageal inflammation but has been elusive to model in animals. Herein, we have generated the first transgenic mouse model of Barrett’s esophagus through overexpression of interleukin-1ß (IL-1β). IL-1β overexpression in the mouse esophageal mucosa induces chronic inflammation that progresses to intestinal metaplasia, with characteristic expression of TFF2, Bmp4 and Cdx2. With aging, IL-1b transgenic mice progress to esophageal adenocarcinoma (EAC) but the process is markedly accelerated by exposure to bile acids and/or nitrosamines, resembling the human counterpart. Moreover, progenitor cells present in the gastric cardia, but absent from the esophagus in humans and mice, are increased in BE, suggesting the cell of origin in the gastric cardia
Project description:genome-wide methylation profile of 250 samples including 125 EAC, 19 Barrett’s, 64 normal adjacent squamous and 21 normal stomach. Transcriptome data was performed for 70 samples with methylation profile (48 EAC, 4 Barrett’s and 18 normal adjacent squamous). This is the first study to use methylome, transcriptome and ENCODE data to characterize the regulatory role of methylation in EAC.
Project description:genome-wide methylation profile of 250 samples including 125 EAC, 19 Barrett’s, 64 normal adjacent squamous and 21 normal stomach. Transcriptome data was performed for 70 samples with methylation profile (48 EAC, 4 Barrett’s and 18 normal adjacent squamous). This is the first study to use methylome, transcriptome and ENCODE data to characterize the regulatory role of methylation in EAC.
Project description:Barrett’s esophagus (BE) is a metaplastic precursor lesion of esophageal adenocarcinoma (EA), the most rapidly increasing cancer in western societies. While the prevalence of BE is increasing, the vast majority of EA occurs in patients with undiagnosed BE. Thus, we sought to identify genes that are altered in BE compared to the normal mucosa of the esophagus, and which may be potential biomarkers for the development or diagnosis of BE. We performed gene expression analysis using HG-U133A Affymetrix chips on fresh frozen tissue samples of Barrett’s metaplasia and matched normal mucosa from squamous esophagus (NE) and gastric cardia (NC) in 43 BE patients.
Project description:Helicobacter pylori is a well-recognized bacterium associated with the development of several histopathological lesions in the stomach. The chronic infection produces an inflammatory lesion known as gastritis. This lesion can later progress to more serious lesions such as intestinal metaplasia. Some attempts in the transcriptome of these conditions have been made; these however, have yielded limited information. Given the potential of high-throughput technologies for understanding biological processes altered and in the description of biomarkers of disease, we performed a genome-wide gene expression analysis in gastric biopsies. The aim of this study was to describe the altered molecular mechanism and potential biomarkers of follicular gastritis, chronic gastritis and intestinal metaplasia, through the identification of characteristic gene expression profiles in each histopathological lesion. The exploratory set comprised twenty-one biopsies from patients with follicular gastritis (n=7), chronic gastritis (n=7), and intestinal metaplasia (n=7), which were analyzed by whole-genome gene expression microarrays. The enrichment analyses and functional annotation of genes using computational tools were performed. The bioinformatics data of the same 21 biopsies were validated by real time PCR analysis while 79 FFPE samples were analyzed by immunohistochemistry. Gene expression analyses showed profiles for each histopathological lesion. Follicular gastritis had an expression profile with marked enrichment of immunologically-related genes. In contrast, chronic gastritis was characterized by a deregulation of mitochondrial-related genes and a down regulation of genes associated with protection against oxidative stress. Meanwhile, intestinal metaplasia showed an over expression of gastrointestinal stem cell markers and molecules related to RNA metabolism. Our results provide a comprehensive and reliable gene expression analysis of follicular gastritis, chronic gastritis and intestinal metaplasia disorders. The gene expression patterns described established a clear difference between the three pathologies studied and allowed the identification of several potential biomarkers for each histological change.
Project description:To test the hypothesis that there is a specific miRNA expression signature which characterizes Barrett's esophagus development and progression, we performed miRNA microarray analysis comparing normal esophageal squamous epithelium with the two different metaplastic lesions occuring within Barrett's mucosa (i.e. gastric metaplasia and intestinal metaplasia). Samples of H. pylori-related gastritis and gastric intestinal metaplasia were also considered in the definition of esophageal-specific miRNAs. miRNA microarray analysis was performed in a series of samples obtained from (a) 10 histologically-proven long-segment Barrett's esophagus patients; (b) 10 patients with H. pylori-related chronic atrophic gastritis. Overall, 10 normal esophageal squamous epithelium samples, 10 esophageal intestinal metaplasia samples, 10 esophageal gastric metaplasia samples, 10 H. pylori -related gastritis samples (no atrophic lesion detected; obtained from the antrum) and 10 gastric intestinal metaplasia samples (obtained from the antrum) were considered.
Project description:Esophageal adenocarcinoma arises from Barrett’s esophagus, a precancerous metaplastic replacement of squamous by columnar epithelium in response to chronic inflammation. Multi-omics profiling, integrating single-cell transcriptomics, extracellular matrix proteomics, tissue-mechanics and spatial proteomics of 64 samples from 12 patients’ paths of progression from squamous epithelium through metaplasia, dysplasia to adenocarcinoma, revealed shared and patient-specific progression characteristics. The classic metaplastic replacement of epithelial cells was paralleled by metaplastic changes in stromal cells, ECM and tissue stiffness. Strikingly, this change in tissue state at metaplasia was already accompanied by appearance of fibroblasts with characteristics of carcinoma-associated fibroblasts and of an NK cell-associated immunosuppressive microenvironment. Thus, Barrett’s esophagus progresses as a coordinated multi-component system, supporting treatment paradigms that go beyond targeting cancerous cells to incorporating stromal reprogramming.
Project description:Alternatively-activated macrophages (M2) are known to play a critical role in intestinalization of spasmolytic polypeptide-expressing metaplasia (SPEM), which is a precursor to gastric adenocarcinoma. However, the precise mechanism(s) and critical mediators produced by M2 macrophages that lead to SPEM are unknown. Using established murine models of metaplasia in the stomach, the aim of the present study was to determine how M2 macrophages induce intestinalized SPEM. Macrophages from the stomach corpus of mice with SPEM (DMP-777-treated) or advanced intestinalized SPEM (L635-treated) were isolated and RNA sequencing was performed. IL-33 was the most upregulated cytokine in macrophages associated with intestinalized SPEM. L635-treated IL-33 knock out mice did not develop metaplasia, suggesting that IL-33 is required for the induction of SPEM after acute parietal cell loss. While the loss of IL-33 did not reduce macrophage recruitment into the mucosa, infiltrating macrophages were not M2 polarized. We conclude that IL-33 is necessary for both the induction of mucous metaplasia (SPEM) in the stomach and polarization towards M2 in recruited macrophages. Our data suggest that the inflammatory pathway in the stomach after parietal cell loss resembles pathways associated with allergy-induced airway inflammation, which implicates novel treatment options for gastritis patients to prevent gastric cancer.