Pathways influencing expression of the immunophilin family of co-chaperones in ALK+ ALCL. The transcription of Cyp40 is promoted by signals initiated by NPM-ALK, and we postulate that up-regulation of JunB by NPM-ALK accounts for much of the increase in Cyp40 transcription. However, additional signalling pathways activated by this oncoprotein likely also contribute to Cyp40 expression. The transcription of FKBP52 is promoted by NPM-ALK in ALK+ ALCL, but in a manner that is independent of JunB. Although expressed in ALK+ ALCL, FKBP51 expression is not regulated by NPM-ALK or JunB in this lymphoma.