Fig. 5.

Cisplatin-induced hydroxyl radicals mediate autophagy in human lung cancer cells. a Pretreatment with the hydroxyl radical scavenger, deferoxamine (1 mM), reverted the alteration of autophagy-regulating proteins (Atg3 and Atg7) expression levels induced by cisplatin, as evidence by western blot analysis. b Significant increment in the LC3-II/LC3-I ratio, and increased Atg3 and Atg7 and decreased expression of p62 by cisplatin treatment was also abrogated by deferoxamine pretreatment. c Fluorescence microscopy demonstrated no accumulation of autophagosomes and autolysosomes, as detected by monodansylcadaverine (MDC) and acridine orange staining, respectively, in non-treated control and deferoxamine-pretreated cells. Notably, staining with acridine orange indicates green fluorescence of cytoplasm and nucleolus while bright red/orange-red fluorescence of acridine orange represents acidic compartment. Data are shown as the mean ± SD (n = 3). *p < 0.05 versus untreated control cells. ^#p < 0.05 versus only cisplatin-treated cells