Fig. 3

SIRT7 promotes prostate cancer cell autophagy and aggressiveness in vitro. a Transmission electron micrographs showing autophagic vacuoles in 22RV1 cells cultured with 1 nM DHT for 3 days before fixation. Arrows indicate autophagosome structures. Scale bar, 1 μm. b Western blot analysis to determine LC3BI/II levels of LNCaP and 22RV1 cells treated with vehicle or DHT (1 nM) for 3 days. c LNCaP and 22RV1 cells stably expressed the mRFP-GFP-LC3 protein and treated for 3 days with vehicle or DHT (1 nM). Autophagosomes (yellow) and autolysosomes (red) was co-visualized and examined by immunofluorescence microscopy. d and e Mean number of puncta of each cell (n = 16 cells) was analyzed and plotted. f Transwell migration and invasion assays showing the effects of SIRT7 on prostate cancer cell migration and invasion. g Apoptosis was analyzed via flow cytometry. h Percent apoptosis was determined in Q3. Each assay was performed in triplicate and the data are shown as the means ± SD. P-values were calculated by t-test (*P < 0.05; **P < 0.01; ***P < 0.001)