Abstract
BACKGROUND: Gastric cancer (GC) is the fifth most common malignant tumor, and it is usually fatal. Adenocarcinoma of the esophagogastric junction (AEG) accounts for about 50% of all GC cases. However, the systematic co-expression analysis of this tumor does not fully explain its pathogenesis. This study aimed to identify hub genes based on weighted gene co-expression networks and immunohistochemistry analyses. METHODS: The RNA-seq data of 22 AEG patients were processed using weighted gene co-expression network analysis. We differentiated the modules with clinical tumor markers and performed Gene Ontology and pathway enrichment analysis. We identified the hub genes related to the biological processes of tumorigenesis based on weighted gene co-expression network analysis and immunohistochemistry analysis. RESULTS: Twenty-five distinct co-expression gene modules were identified; the tumorigenic genes CD93, TRIM28, SLC3A2, CBX4, PATL1, and ZNF473 had high intramodular connectivity. Immunohistochemistry confirmed that these hub genes are upregulated in AEG. Statistical analysis indicated that the expression of CD93 was correlated with the T stage and maximum tumor diameter. CONCLUSION: Weighted gene co-expression network analysis and immunohistochemistry identified CD93 as a hub gene that might be critical for AEG biology.