This study revealed that 11-(1,4-Bisaminopropylpiperazinyl)5-methyl-5H-indolo[2,3-b]quinoline (BAPPN) has cytotoxic potential against liver, colon, breast, and lung cancer cell lines via activation of caspase-3 and p53, and deactivation of PCNA, Ki67, and VGEF protein expression. The gene discussed is MKI67; the disease is lung cancer.