Single-cell RNA sequencing revealed heterogeneity of the immune microenvironment in gastric cancer

Tumor microenvironment (TME) cells constitute a critical component of tumor tissues, and mounting evidence has highlighted their clinicopathological significance in predicting patient outcomes and therapeutic efficacy. Single-cell RNA sequencing (scRNA-seq) enables a comprehensive analysis of diverse cell types within tumors across various biological states and conditions, offering deeper insights into immune profiles. In this study, we systematically searched publicly available scRNA-seq gene expression datasets related to gastric cancer and collected a total of 458,150 cells from 109 samples, including primary gastric cancer, metastatic cancer, paired para-cancerous normal tissues, and peripheral blood. We then investigated the TME of primary and metastatic gastric cancer, analyzing cellular composition, differential gene expression, pseudo-time trajectories, and intercellular interactions. Our findings reveal the pivotal role of T cells, B cells, and macrophages in shaping the heterogeneous TME across different samples. This comprehensive characterization of immune heterogeneity in gastric cancer provides valuable insights for designing personalized therapeutic strategies in clinical practice.