Although the mechanism was unclear, a number of recent researches had shown that Notch1 activation could induce the expression Hes3 and sonic hedgehog (Shh) by activating cytoplasmic serine/threonine kinase Akt, signal transducer and activator of transcription 3 (ATAT3), and mammalian target of rapamycin (mTOR), promoting the survival of neural stem cells and inducing brain cancer [18]. Here, STAT3 is linked to brain cancer.