There is a close relationship between the Nrf2–ARE signaling pathway and cancer cell apoptosis.37,38 For evaluating the effect of PBQC on Nrf2 activity, we used luciferase HeLa cells which can stably express firefly luciferase to immediately monitor the change of Nrf2 activity.38 Luciferase activity was detected after incubating cells with compound PBQC at indicated concentrations for specified time durations. Here, NFE2L2 is linked to cancer.