Representative AO&PI and FDA&PI staining images of A549 and U87MG cells treated with tocotrienols. Following a treatment period of 24 h, (A,E) untreated vehicle control cells show normal appearance with no prominent apoptotic and necrotic cells. In AO&PI staining, A549 and U87MG cells treated with IC50 of (B) alpha-, (C) gamma- and (D) delta-tocotrienols show early apoptosis exhibiting a bright-green nucleus as condensation of chromatin (white arrows), and late apoptosis demonstrating cellular blebbing and nuclear margination (white and red arrowhead). FDA&PI stained A549 and U87MG cells treated with IC50 of (F) alpha-, (G) gamma- and (H) delta-tocotrienols show cell death with higher red fluorescence evidenced as compared to the untreated cells (E). Bar (AO&PI): 10 μm; Bar (FDA&PI): 50 μm; α-T3: alpha-tocotrienol; γ-T3: gamma-tocotrienol; δ-T3: delta-tocotrienol.