Azacitidine (DNA methyltransferase inhibitor) 51, ISOX (HDAC inhibitor) 52, ascorbic-acid (antioxidant) 53, cosmosiin (cytochrome P450 inhibitor) 54, IB-MECA (adenosine receptor agonist) 55, fostamatinib (SYK inhibitor) 56, and iloprost (platelet aggregation inhibitor) 57 have been used as a treatment or providing protective effects for IBD. Here, HDAC9 is linked to inflammatory bowel disease.