We previously confirmed that FGF9 expression is increased in severe fatty liver, although it is relatively low in normal liver tissue, suggesting that FGF9 may play an important role in regulating hepatic metabolic homeostasis.[19] Therefore, we sought to determine whether FGF9 expression is induced in response to different stimuli that activate several metabolic processes in liver cells. This evidence concerns the gene FGF9 and digestive system neoplasm.