No increase in DNA strand breaks was induced in the noncancerous NCM460 colon epithelial cells (Supplementary Figures S2B,C), and both the comet tails and 53BP1 foci in the cancer cells were effectively reversed by NAC (Figures 2B,C; Supplementary Figure S2C), indicating that the DNA strand breaks resulted from sublethal alkannin-induced ROS elevation. This evidence concerns the gene TP53BP1 and cancer.