Figure 5.

(a) Hyperinduced autophagic cells by 10 Gy of X-rays in parental HepG2 and radioresistant HepG2-8960-R cells. The induction level of hyperinduced autophagic cells in HepG2-8960-R was lower than that in HepG2. (b) Hyperinduced autophagic cells by fractionated 2 Gy of X-rays. Hyperinduced autophagic cells of HepG2 were gradually increased along with the dose. No increase in hyperinduced autophagic cells was observed in HepG2-8960-R after exposure to total 10 Gy of X-rays. Mean±S.D. of three independent experiments. ^**P<0.01, ^*P<0.05 compared with control. (c) Western blot analysis of LC3 protein after X-irradiation. At day 5 after exposure to 10 Gy of X-rays, the increase in LC3-II, a hallmark of the induction of autophagy, was observed in both parental HepG2 and radioresistant HepG2-8960-R, and the amount of LC3-II in HepG2 was higher than that in HepG2-8960-R. (d) Western blot analysis of p62 protein after X-irradiation. At day 5 after exposure to 10 Gy of X-rays, the reduction of p62 protein, a hallmark of the induction of autophagy, was observed in both parental HepG2 and radioresistant HepG2-8960-R, and the amount of p62 protein in HepG2 was reduced much more than that in HepG2-8960-R