BMI1 and pituitary tumor: MiR-26b (targeting PTEN) is upregulated and miR-128 (targeting BMI1) is down-regulated in GH-PTs compared to control and is shown to mediate growth and invasiveness of pituitary tumor cells (265). MiR-338-3p expression is increased in invasive GH-PTs and is mediated through upregulation of PTTG1 (266).