posted on 2023-06-02, 08:20authored byKarol Nowicki-Osuch, Lizhe Zhuang, Tik Shing Cheung, Emily L. Black, Neus Masqué-Soler, Ginny Devonshire, Aisling M. Redmond, Adam Freeman, Massimilliano di Pietro, Nastazja Pilonis, Wladyslaw Januszewicz, Maria O'Donovan, Simon Tavaré, Jacqueline D. Shields, Rebecca C. Fitzgerald
<p>E-GM and atrophic gastritis share early features of developing IM. <b>A,</b> UMAP of columnar cells of gastric cell types (NGC and NGB, top left), E-GM (top right), and atrophic gastritis (NAG and CAG, bottom left) with cell-type annotation highlighted. Bottom right, UMAP with clusters 6 and 16 (identified during reclustering of columnar cells and overlapping gastric neck cells) highlighted. EE, enteroendocrine. <b>B,</b> Stacked bar chart of tissue contribution to the cells assigned to clusters 6 and 16. <b>C,</b> Gene set enrichment analysis (GSEA) using the C3 gene set database of differentially expressed genes between neck-like cells from E-GM and NGC samples. HNF4A- and MYC-related pathways are highlighted. The differential analysis was done between E-GM cells and NGC + NSCJ neck-like cells with each patient treated as an individual replicate. NES, normalized enrichment score. <b>D,</b> GSEA using the C3 gene set database of differentially expressed genes between NAG/CAG and NGC/NGB/NSCJ sample neck-like cells. AP-1–related pathways are highlighted. The differential analysis was done between cluster 16 cells (including NAG, CAG, and E-GM cells) and cluster 6 (including NGC + NGB + NSCJ neck-like cells) with each patient treated as an individual replicate. <b>E,</b> Venn diagram demonstrating the overlap between genes enriched in the comparison of atrophic gastritis (NAG and CAG) and normal gastric samples or E-GM and normal gastric samples. Bottom left: bubble plot of top 25 expressed genes shared between the comparison. Bottom right, violin plots of selected genes. <b>F,</b> WGS-based analysis of E-GM and BE-IM. Top, mutational burden [single-nucleotide variants/megabase (SNV/Mb)] of NGC, E-GM, and BE-IM samples. Bottom, distribution of COSMIC SNV signatures in the E-GM and BE-IM samples.</p>
Funding
Cancer Research UK (CRUK)
Medical Research Council (MRC)
Foundation for Canadian Studies in the United Kingdom (Canada-UK Foundation)
Intestinal metaplasia in the esophagus (Barrett's esophagus IM, or BE-IM) and stomach (GIM) are considered precursors for esophageal and gastric adenocarcinoma, respectively. We hypothesize that BE-IM and GIM follow parallel developmental trajectories in response to differing inflammatory insults. Here, we construct a single-cell RNA-sequencing atlas, supported by protein expression studies, of the entire gastrointestinal tract spanning physiologically normal and pathologic states including gastric metaplasia in the esophagus (E-GM), BE-IM, atrophic gastritis, and GIM. We demonstrate that BE-IM and GIM share molecular features, and individual cells simultaneously possess transcriptional properties of gastric and intestinal epithelia, suggesting phenotypic mosaicism. Transcriptionally E-GM resembles atrophic gastritis; genetically, it is clonal and has a lower mutational burden than BE-IM. Finally, we show that GIM and BE-IM acquire a protumorigenic, activated fibroblast microenvironment. These findings suggest that BE-IM and GIM can be considered molecularly similar entities in adjacent organs, opening the path for shared detection and treatment strategies.
Our data capture the gradual molecular and phenotypic transition from a gastric to intestinal phenotype (IM) in the esophagus and stomach. Because BE-IM and GIM can predispose to cancer, this new understanding of a common developmental trajectory could pave the way for a more unified approach to detection and treatment.See related commentary by Stachler, p. 1291.This article is highlighted in the In This Issue feature, p. 1275