A number of studies have also shown the importance of STAT3 in the inflammatory response to diseases as well as immune response such as inducing pro-inflammatory gene cyclooxygenase 2 expression to regulate TLR4-mediated inflammation in early and late phases, accelerating the development of colitis by the deficiency of STAT3 in hematopoietic cells leads, and involving in the inflammatory bowel disease and bacterial infections [25,26]. The gene discussed is PTGS2; the disease is colitis.