Figure 5
From: NDRG1 inhibition sensitizes osteosarcoma cells to combretastatin A-4 through targeting autophagy
NDRG1 knockdown impairs lysosomal function in OS cells. (a) MG63.2 cells were stained with NDRG1 and LAMP1 antibodies in the presence or absence of CQ. The colocalization of NDRG1 and LAMP1 was examined by the confocal microscopy, scale bars: 10 μm. (b) Immunoblotting analysis of LAMP1 in MG63.2 cell with NDRG1 knockdown. (c and d) NDRG1 knockdown interferes with the acidification of lysosomes. MG63.2 cells transfected with control nontarget or NDRG1 siRNA were exposed to LysoTracker for confocal microscopy. (e) Lysosomal pH values were measured using a quantitative ratiometric LysoSensor Yellow/Blue DND-160. Scale bars: 500 nm. (f) Enzymatic activity of CTSB was measured in MG63.2 cells transfected with control nontarget or NDRG1 siRNA using fluorogenic kits. (g) MG63.2 cells transfected with control or NDRG1 siRNA were treated with 50 ng/ml EGF, and EGFR, p-AKT and p-ERK were determined at each point by immunoblotting. (h) The EGFR bands in g were quantified and normalized according GAPDH. The data were presented as mean±S.D (*P<0.05, n=3)
