Accumulating evidence suggests that exposure to β-lap causes DNA lesions in NQO1+ NSCLC, breast cancer, and pancreatic cancer cells, resulting in PARP hyperactivation in terms of the accumulation of poly(ADP-ribose)-PARP (PAR-PARP) posttranslational protein modification (11, 18, 24). This evidence concerns the gene PARP1 and breast cancer.