JUN and inflammatory bowel disease: Previous studies demonstrated (1) the up-regulation of JunB (approximately 1.5-fold) in colon biopsies from CD patients [37]; (2) the up-regulation of Fra-1 in bone from IBD model rats [38]; and (3) the up-regulation of c-Fos, but not c-Jun or JunB in the colons of UC patients [39].