OBJECTIVES

Gastric cancer is the second leading cause of cancer-related death worldwide. Gene expression profile facilitates the identification of molecular mechanism of gastric cancer. Previous studies mainly focused on differentially expressed genes (DEGs) without considering MicroRNAs (miRNAs) and transcription factors (TFs). Here we aim to elaborate the mechanism of gastric cancer on transcription level with microarray data from the gene expression omnibus (GEO) database.

MATERIALS AND METHODS

We firstly identified DEGs between gastric cancer and normal tissues. Then the DEGs were mapped in KEGG pathway and gene ontology database to conduct functional categories enrichment analysis. MiRNAs and TFs enriched with target DEGs were also identified.

RESULTS

A total of 977 DEGs were selected, including 492 down regulated and 485 overexpressed genes in gastric cancer tissue. Functional analysis revealed cell cycle, metabolism and ECM related biological processes as the significant items. Eight miRNAs and 20 TFs enriched with target DEGs were detected, including one novel miRNA (miR-557) and four novel TFs (SPI1, NFIC, SPIB and THAP1), which have not been reported to be related to gastric cancer before. All of them might contribute to the pathogenesis since they are all related to other cancers and their target genes have been reported to play important roles in gastric tumorigenesis.

CONCLUSIONS

Our results may facilitate further therapeutic studies of gastric cancer.