The treatment of A549 cells with Mito-TEMPO significantly reversed both the ABN-B-induced up-regulation of p21 and the down-regulations of cyclin B1 and CDK1 (Figure 5C), suggesting that ABN-B could induce cell cycle arrest at the G2/M phase in human lung cancer cells via mitochondrial ROS generation. This evidence concerns the gene CDKN1A and lung carcinoma.