As shown in Figure 3, the down-regulation of NOXA significantly reduced Annexin V-positive (Figure 3A) and caspase-3 positive (Figure 3B) cell populations as well as the expression of cleaved PAPR induced by MLN4924+CQ treatment (Figure 3C), indicating a causal role of NOXA expression in MLN4924+CQ triggered apoptosis in liver cancer cells. This evidence concerns the gene PMAIP1 and liver cancer.