E2F1 and pituitary tumor: miR-23b and miR-130b, targeting HMGA2 and cyclin A2 respectively, are downregulated in GH-PTs, GT-PTs and NFPTs (233). HMGA2 is a high mobility group protein, which shows increased expression in pituitary tumors (234, 235). HMGA2 overexpression enhances E2F1 activity and drives cell cycle (236, 237) microRNAs targeting HMGA2 and E2F1 are downregulated in pituitary tumors (235, 238).