Specifically, we analyzed the upregulation of PLAB and the cleavage of caspase-3 for the activation of the ROS-induced apoptotic cascade and the accumulation in G2-M phases of the cell cycle for the antimitotic activity in STO (mesothelioma cells derived from a patient’s surgical specimen), IGROV-1 (ovarian cancer cell line), and MDA-MB-231 (triple negative breast cancer cell line) cells. The gene discussed is CASP3; the disease is mesothelioma.