STAT3 and cancer: Brusatol may abrogate gemcitabine-induced NRF2 activation in pancreatic cancer cells to restore chemosensitivity of cancer cells [48]; may enhance the radiosensitivity of lung cancer cells by promoting ROS production and enhancing DNA damage [49]; and may inhibit cancer cell growth and induce apoptosis via JNK/p38 MAPK/NF-κb/Stat3/Bcl-2 [50].