Chemo-resistant Gastric Cancer Associated Gene Expression Signature: Bioinformatics Analysis Based on Gene Expression Omnibus

Background/Aim: This study aimed to identify biomarkers for predicting the prognosis of advanced gastric cancer patients who received docetaxel, cisplatin, and S-1 (DCS). Materials and Methods: Gene expression profiles were obtained from the Gene Expression Omnibus database (GSE31811). Gene-Ontology-enrichment and KEGG-pathway analysis were used for evaluating the biological functions of differentially-expressed genes. Protein-protein interaction (PPI) network and Kaplan-Meier survival analyses were employed to assess the prognostic values of hub genes. Results: A total of 1,486 differentially expressed genes (DEGs) were identified, including 13 up-regulated and 1,473 down-regulated genes. KEGG pathways such as metabolic pathways, cell adhesion molecules (CAMs), PI3K-Akt signaling pathway and pathways in cancer were significantly represented. In the PPI network, the top ten hub genes ranked by degree were GNG7, PLCB1, CALML5, FGFR4, GRB2, JAK3, ADCY7, ADCY9, GNAS and KDR. Five DEGs, including ANTXR1, EFNA5, GAMT, E2F2 and NRCAM, were associated with relapse-free survival and overall survival. Conclusion: ANTXR1, EFNA5, GAMT, E2F2 and NRCAM are potential biomarkers and therapeutic targets for DCS treatment in GC.