Analysis of single-cell RNA sequencing data to examine the gastric inflammation-to-cancer transition and evaluation of the effect of probiotic on precancerous lesions

• PR-enriched pit mucous cells drive the inflammation-to-cancer transition. • Gene set was rigorously validated across multiple external cohorts. • Probiotics modulate the gastric cancer-associated tumor-immune microenvironment. Gastric cancer (GC) is the fifth most prevalent malignancy globally. However, its heterogeneity and asymptomatic early-stage development hinder timely diagnosis and effective treatment. Here, we employed single-cell RNA sequencing to delineate the transitional features of pit mucous cells (PMCs) during the gastritis-to-cancer transition and identified 100 core genes. Characterization of the gene set revealed the role of ribosomal protein small subunit and ribosomal protein large subunit in inflammation-to-cancer transition, which promoted ribonucleoprotein complex biogenesis and cytoplasmic translation. External validation using independent cohorts confirmed that this core gene set discriminated disease progression (AUC > 0.7) and was significantly enriched in GC tissues ( p < 0.01). Moreover, we evaluated the therapeutic intervention effects of C. butyricum and synbiotics (Weichanghao®) using a rat model of gastritis and demonstrated the targeted suppression of inflammation-to-cancer transition genes. Our findings establish the basis for early diagnosis of GC through PMC-driven molecular dynamics. Additionally, we propose microbiota-based strategies to prevent the inflammation-to-cancer transition in preneoplastic stages. Furthermore, our results highlight that dysbiosis of the gastric microbiome can be addressed using probiotic supplementations and the core gene set may provide labeling for the evaluation of probiotics-based treatment.