Fig. 1

SPD induces autophagy of FGSCs and enhances autophagic flux. A LC3B, p62, and β-tubulin (control for loading) protein expression levels in FGSCs treated with SPD (100 μM) for different times. *P < 0.05, ***P < 0.001 compared with controls. Western blot analysis was performed to detect LC3B and β-tubulin protein levels in FGSCs pretreated with B 3-MA (5 mM) or C CQ (20 μM) for 1 h, followed by exposure to SPD (100 μM) for another 4 h. Numbers below the dots correspond to relative quantification by densitometry compared with the reference point set to 1. D Immunofluorescence images of LC3B puncta in FGSCs pretreated with inhibitors of autophagy (3-MA or CQ) followed by exposure to SPD (100 μM) for another 4 h. The number of LC3B puncta per cell was the highest in co-incubation of cells with SPD and CQ treatment (scale bars: 20 μm). E Fluorescence microscopic examination of FGSCs expressing a tandem GFP-RFP-LC3 fusion protein that were treated with SPD with or without CQ (20 μM) for 4 h (scale bars: 50 μm). Con control