Figure 4.

α-Mangostin is synergistic with retinoic acid on inhibiting apoptosis-related genes and AKT signaling pathway. (A) The expression of cleaved PARP and PARP were analyzed by Western blot in sk-mel-2 cells exposed to retinoic acid (2 μM) in either the presence or absence of α-Mangostin (5 μM) for 8 h. The expression of cleaved PARP was increased with the combination of retinoic acid and α-Mangostin. (B) As anti-apoptotic proteins, MCL-1 and P21 expression levels were suppressed with retinoic acid (2 μM) and α-Mangostin (5 μM) treatment for 8 h in sk-mel-2 cells. (C) Down-regulation of phosphorylation of AKT and S6 is much more significant within 2 h after the treatment with the combination of retinoic acid (2 μM) and α-Mangostin (5 μM) than by single agents.