CHAC1 and nasopharyngeal carcinoma: Wang et al found that glaucocalyxin A activates ROS-mediated ATF4/CHOP/CHAC1 signaling, thereby inhibiting proliferation and inducing apoptosis in the oral squamous cell carcinoma cell lines SCC25 and CAL27.[9] Tetrandrine can induce cell apoptosis in NPC-TW 039 human nasopharyngeal carcinoma cells by activating ERS stress related protein GADD153 and the expression of GRP78 through elevated intracellular Ca2+.