Bile reflux is considered to be one of the most important causative factors in gastric carcinogenesis, due to the attendant inflammatory changes in the gastric mucosa. In this study, we have assessed the molecular mechanisms inherent to the contribution of bile acid to the transcriptional regulation of inflammatory-related genes. In this study, we demonstrated that bile acid induced the expression of the SHP orphan nuclear receptor at the transcriptional level via c-Jun activation. Bile acid also enhanced the protein interaction of NF-kappaB and SHP, thereby resulting in an increase in c-Jun expression and the production of the inflammatory cytokine, TNFalpha. These results indicate that bile acid performs a critical function in the regulation of the induction of inflammatory-related genes in gastric cells, and that bile acid-mediated gene expression provides a pre-clue for the development of gastric cellular malformation.