The human pituitary proteome: the characterization of differentially expressed proteins in an adenoma compared to a...

In order to clarify the basic molecular mechanisms that participate in the formation of human pituitary macroadenomas, this study, for the first time, describes the comparative proteomics between a pituitary adenoma tissue and a control tissue. A vertical, two-dimensional polyacrylamide gel electrophoresis system and PDQuest image analysis software were used to provide a high level of between-gel reproducibility and electrophoretic separation to accurately locate each differentially expressed protein. Mass spectrometry (MALDI-TOF and LC-ESI-Q-IT) and protein databases were used to characterize each differentially expressed protein. A total of 137 differential gel spots (37 increased spot volumes, 39 decreased, 19 new and 42 lost) were found when we compared an adenoma proteome to a control proteome. Seventy-one spots (20 increased, 27 decreased, 13 new, 11 lost), representing 39 differentially regulated proteins, were identified. Five differentially regulated proteins (prolactin, cellular retinoic acid-binding protein II, G-protein beta subunit 3, secretagogin and calreticulin) were also validated with results from a comparative transcriptomics study of pituitary adenomas and controls. The functional characteristics of these differentially expressed proteins provide a differential proteomic profile between a pituitary adenoma and a control.