COL1A1, COL1A2, CHN1, and FN1 Promote Tumorogenesis and Act as Markers of Diagnosis and Survival in Gastric Cancer Patients.

Objectives: This study aimed to comprehensively investigate the molecular landscape of gastric cancer (GC) by integrating various bioinformatics tools and experimental validations.

Methodology: GSE79973 dataset, limma package, STRING, UALCAN, GEPIA, OncoDB, cBioPortal, DAVID, TISIDB, Gene Set Cancer Analysis (GSCA), tissue samples, RT-qPCR, and cell proliferation assay were employed in this study.

Results: Analysis of the GSE79973 dataset identified 300 differentially expressed genes (DEGs), from which COL1A1, COL1A2, CHN1, and FN1 emerged as pivotal hub genes using protein-protein interaction network analysis. Subsequent validation across The Cancer Genome Atlas (TCGA) datasets confirmed their up-regulation in GC tissues compared to normal controls. Promoter methylation analysis revealed decreased methylation levels of these hubs in GC tissues, suggesting their potential role in tumorigenesis. Mutational analysis using cBioPortal showcased frequent mutations in these genes, particularly FN1, further highlighting their significance in GC pathogenesis. Survival analysis indicated their correlation with reduced overall survival rates among GC patients, supported by the development of a robust prognostic model. Prediction of hub-associated miRNAs and gene enrichment analysis provided insights into their regulatory mechanisms and downstream pathways, implicating their involvement in extracellular matrix remodeling and cell migration. Drug sensitivity analysis revealed correlations between hub gene expression and drug response, while RT-qPCR validation confirmed their upregulation in clinical GC samples. Finally, functional assays demonstrated the impact of FN1 knockdown on cellular proliferation, colony formation, and wound healing capacities.

Conclusion: Overall, this study elucidates the crucial role of COL1A1, COL1A2, CHN1, and FN1 in GC pathogenesis and underscores their potential as diagnostic markers and therapeutic targets.