EIF4E and ACTH-producing pituitary gland adenoma: In a study on 53 pituitary samples obtained from patients (including GHomas, NFPAs, ACTHomas), mTOR kinase activity, estimated as pS6rp/eIF4E ratio, was elevated in pituitary adenomas and especially active in GHomas, which had the highest level of mTOR activity, which was statistically significant in comparison to NFPA [116].