NQO1 and lung carcinoma: Coroglaucigenin, a cardenolide isolated from the EtOAc fraction of an extract prepared from the stems and leaves of C. gigantea effectively induced apoptosis in human lung cancer cells through the inhibition of antioxidant molecules (NAD(P)H dehydrogenase [quinone] 1, heme oxygenase 1), leading to the accumulation of ROS [19].