RESEARCH ARTICLE Transcription Factors and microRNA-Co- Regulated Genes in Gastric Cancer Invasion in Ex Vivo

Aberrant miRNA expression abnormally modulates gene expression in cells and can con-tribute to tumorigenesis in humans. This study identified functionally relevant differentially expressed genes using the transcription factors and miRNA-co-regulated network analysis for gastric cancer. The TF-miRNA co-regulatory network was constructed based on data ob-tained from cDNA microarray and miRNA expression profiling of gastric cancer tissues. The network along with their co-regulated genes was analyzed using Database for Annotation, Visualization and Integrated Discovery (DAVID) and Transcriptional Regulatory Element Database (TRED). We found eighteen (17 up-regulated and 1 down-regulated) differentially expressed genes that were co-regulated by transcription factors and miRNAs. KEGG path-way analysis revealed that these genes were part of the extracellular matrix-receptor inter-action and focal adhesion signaling pathways. In addition, qRT- PCR andWestern blot data showed an increase in COL1A1 and decrease in NCAM1 mRNA and protein levels in gas-tric cancer tissues. Thus, these data provided the first evidence to illustrate that altered gene network was associated with gastric cancer invasion. Further study with a large sam-ple size and more functional experiments is needed to confirm these data and contribute to diagnostic and treatment strategies for gastric cancer