Single-cell Sequencing Analysis Of Gastric Mucosa Malignant Induction Model In Mouse

Background and ObjectiveAmong malignant tumors in the world,the incidence rate of gastric cancer is the fifth and the mortality rate is the third.In China,the incidence and mortality of gastric cancer are both in the top three,and it is one of the highly lethal diseases affecting human health and life expectancy.Gastric adenocarcinoma is the most common subtype of gastric cancer in China.It has a distinct progressive evolution process,and Helicobacter pylori plays an important role in the occurrence and evolution of gastric adenocarcinoma.Gastric adenocarcinoma is a complex disease with high heterogeneity.The inter and intra-tumor heterogeneity brings great challenges to the diagnosis,treatment and prognosis of gastric adenocarcinoma.Therefore,in-depth exploration of tumor microenvironment and intra-tumor heterogeneity is of great significance for improving the detection ability of early gastric adenocarcinoma and providing precision medicine for gastric cancer patients.This study aimed to preliminarily establish the single-cell evolution model of gastric mucosa malignant transformation process in mice by using singlecell transcriptome sequencing technology,and lay a foundation for the analysis of gastric cancer microenvironment and its malignant transformation mechanism.Methods and ResultsIn this study,C57BL/6J male mice were selected to be fed with N-methyl-N-nitrosourea,intragastric administration of Helicobacter pylori SS1 strain and chronic restraint stress stimulation to construct a mouse gastric mucosal malignant induction model.Using single-cell RNA sequencing technology,28,137 single cells from the gastric mucosa of 3 experimental mice and 1 control mouse were sequenced.9 different cell types were identified,including 1 intestinal-derived tuft cell subsets.The epithelial cells were extracted and then clustered,and 5 epithelial cell subsets were obtained,including 2 foveolar cell subsets,1 chief cell subset and 2 mucous neck cell subsets.Compared with the control group,the number of chief cell subsets in the gastric mucosa of the experimental group was significantly reduced.The expression of Cdk8,Magi1,Gast and other genes closely related to the occurrence and development of gastric cancer increased in the epithelial cells of the experimental group.In addition,we also found a subset of tumor-associated fibroblasts,whose differential genes were significantly enriched in signaling pathways such as PI3K-Akt,NF-κB,and MAPK.By analyzing the cellular communication between immune cells and five epithelial cell subsets,we found that galectin and macrophage migration inhibitory factor play an important role in the complex cell communication network and can mediate the signal transduction from five epithelial cells subsets to immune cells subset.Conclusion and SignificanceIn this study,we used single-cell RNA sequencing technology to describe the single-cell transcriptome landscape of gastric mucosa malignant induction model in mouse,preliminarily revealed the cell type transformation and molecular changes in the process of gastric mucosal lesions,and analyzed the potential signal transduction mechanism from epithelial cells to immune cells.We discussed the heterogeneity in the process of malignant transformation of epithelial cells,which provided a reference for understanding the mechanism of occurrence and development of early gastric cancer from single cell level.By single-cell sequencing technology,we can study the transcriptome changes during the malignant transformation of epithelial cells into early gastric cancer tumor cells,analyze the complex tumor microenvironment and intratumor heterogeneity,and lay a foundation for exploring the origin of gastric cancer cells.