STAT3 and brain neoplasm: Histology analysis of xenograft brain tumors revealed that the pathologies of GBM-R2I2/sh-STAT3 tumors after 5 Gy RT exhibited dramatically reduced tumor size in 3T MRI compared with those of GBM-R2I2/sh-Scr tumors post-RT (5 Gy) (Figure 6A).