Landscape of four different stages of human gastric cancer revealed by single-cell sequencing.

Abstract

Background: Gastric cancer (GC) poses a substantial risk to human health due to its high prevalence and mortality rates. Nevertheless, current therapeutic strategies remain insufficient. Single-cell RNA sequencing (scRNA-seq) offers the potential to provide comprehensive insights into GC pathogenesis.

Aim: To explore the distribution and dynamic changes of cell populations in the GC tumor microenvironment using scRNA-seq techniques.

Methods: Cancerous tissues and paracancerous tissues were obtained from patients diagnosed with GC at various stages (I, II, III, and IV). Single-cell suspensions were prepared and analyzed using scRNA-seq to examine transcriptome profiles and cell-cell interactions. Additionally, quantitative real-time polymerase chain reaction (qRT-PCR) and flow cytometry were applied for measuring the expression of cluster of differentiation (CD) 2, CD3D, CD3E, cytokeratin 19, cytokeratin 8, and epithelial cell adhesion molecules.

Results: Transcriptome data from 73645 single cells across eight tissues of four patients were categorized into 25 distinct cell clusters, representing 10 different cell types. Variations were observed in these cell type distribution. The adjacent epithelial cells in stages II and III exhibited a degenerative trend. Additionally, the quantity of CD4 T cells and CD8 T cells were evidently elevated in cancerous tissues. Interaction analysis displayed a remarkable increase in interaction between B cells and other mast cells in stages II, III, and IV of GC. These findings were further validated through qRT-PCR and flow cytometry, demonstrating elevated T cells and declined epithelial cells within the cancerous tissues.

Conclusion: This study provides a comprehensive analysis of cell dynamics across GC stages, highlighting key interactions within the tumor microenvironment. These findings offer valuable insights for developing novel therapeutic strategies.