MGMT and pituitary adenocarcinoma: In a recent meta-analysis, in which pituitary carcinomas were compared with aggressive adenomas, a number of factors related to the stimulation of cell growth, angiogenesis, and invasiveness (cyclin D1, VEGF, MMP9, miR-122, and miR-493) were found to be up-regulated, whereas several factors, including growth inhibitors and apoptosis inducers (p16Ink4A, p27Kip1, MT3, BCL-2, Bax, Bcl-X, and O6-methylguanine DNA methyltransferase [MGMT]), were down-regulated95,96.