STAT3 and cancer: As shown in Fig. 1A, the BEZ235-treated cells showed a significant inhibition of the PI3K/AKT/mTOR signaling molecules and an increase in p-STAT3Tyr705 levels, indicating that re-activation of the PI3K/AKT/mTOR pathway in PTEN-deficient cancer cells may involve inhibition of STAT3 activity.