Fig. 4

HMGB1 translocates from the mitochondria to the cytoplasm after sorafenib treatment. HepG2 cells were untreated or treated with 5 μM sorafenib for 48 h. a Nuclear and cytoplasmic proteins were separated, and the expression of HMGB1 in both fractions was examined by western blotting. b HMGB1 expression in extracted mitochondria (Mito) and the remaining cytoplasm without the mitochondria (Cyt) was examined. c HepG2 cells were untreated (Control) or treated with 5 μM sorafenib for 48 h (Treatment), and stained for HMGB1 (red), DAPI (blue), and tomm20 (green) to visualize the mitochondria. Cells were examined by confocal microscopy (magnification, ×630). d Colocalization of HMGB1 with mitochondria in HepG2 cells was analysed in images from three independent experiments (**p < 0.01)