Revealing Inhibition of Gastric Cancer Occurrence and Metastasis by GPX3 Through Single-Cell Transcriptomics and Organoid Multimodal Technologies.

Metastasis is a major factor leading to an unfavorable prognosis in gastric cancer (GC). However, factors driving GC metastasis are not fully understood. Single-cell transcriptome analysis was done on three primary GC samples, one adjacent nontumor sample, and six GC metastasis samples (GSE163558) to clarify cellular composition characteristics, differential genes, and screen genes related to epithelial-mesenchymal transition (EMT). Effects of GPX3 on GC growth and metastasis were assessed through in vitro cell experiments, a GC liver metastasis model, a GC organoid model, and an organoid xenograft nude mouse model. The primary tumor samples showed a higher proportion of epithelial cells, and analysis revealed a significant reduction in GPX3 levels in GC metastasis samples within the subpopulation of epithelial cells undergoing EMT. Cell experiments demonstrated low expression of GPX3 in GC cells, and overexpression of GPX3 inhibited cell migration, invasion, and EMT in GC cells. Further validation in a nude mouse liver metastasis model confirmed the repressive role of GPX3 in GC metastasis. Additionally, GPX3 could inhibit the growth of patient-derived GC organoids and impede tumor growth and metastasis in an organoid xenograft nude mouse model. This study, based on single-cell transcriptome analysis, revealed the potential inhibitory factor GPX3 in metastatic GC and validated its effects on GC growth and metastasis using GC cells and organoids in vitro and in vivo experiments. These findings offer insights into understanding GC heterogeneity and targeting GPX3 in GC therapeutic strategies.