STAT3 and glioblastoma: JAK/STAT signaling is particularly important in the anti-tumor activity of PPARγ agonists because the inhibition of JAK2 (upstream regulator of STAT3) has been shown to have a role in slowing the disease progression of GBM in vivo and in vitro models (30), and troglitazone has been described as an antagonist for STAT3 signaling (31).