Antihepatoma peptide, scolopentide, derived from the centipede scolopendra subspinipes mutilans

Figure 6 Antihepatoma mechanism of scolopentide. A: Flow cytometry suggested that apoptosis occurred in HepG2 cells after treatment with extracted scolopentide in vitro. B-I: Quantitative real-time polymerase chain reaction (qRT-PCR) and western blotting showed that the expression of DR4 (B and C), DR5 (H and I), FADD (E and F), caspase-8 (F and G), and caspase-3 (C and D) was significantly upregulated in the scolopentide group. DR4 was the most considerably upregulated; I-K: qRT-PCR and western blotting showed that the expression of Cyto-C (I and J) and Bax/Bcl-2 (K) was not upregulated, which are key indicators of mitochondria dependence; L: Tumor ROS levels in the scolopentide group were higher than those in the vehicle group; M: c-FLIP, an inhibitory protein of caspase-8, was significantly downregulated in qRT-PCR; N: XIAP, an inhibitory protein of caspase-3, was insignificantly upregulated in qRT-PCR. DR4: Death receptor 4; DR5: Death receptor 5; FADD: Fas-associated death domain protein. n = 4 per group in qRT-PCR, n = 3 per group in Western blotting, n = 4 per group in ROS; ^aP < 0.05, ^bP < 0.01.