Fig. 1

Autophagy marker LC3 expression correlates with CSC marker expression in pancreatic cancer cells. a Pancreatic tumor tissues were immunofluorescently stained for autophagy marker LC3 (green) and CSC markers ALDH1, CD44, and CD133 (red). Samples stained with secondary antibodies alone served as a negative control. Magnification: 800×, scale bar: 20 μm. b Immunofluorescence analysis of LC3, ALDH1, CD44, and CD133 was performed in TMAs. LC3 expression showed a significant positive correlation with ALDH1 (R = 0.849, P < 0.001), CD44 (R = 0.309, P = 0.003), and CD133 expression (R = 0.289, P = 0.005). c PANC-1, MIA PaCa-2, AsPC-1, and SP-1 cells were cultured in ultra-low attachment plates for 14 days to form spheres. The lysates of sphere-forming cells were collected for Western blotting with the indicated antibodies. β-Actin was used as a loading control. The levels of LC3-II were normalized against β-Actin. Values represent the means ± SE of three independent experiments. *, P < 0.05; **, P < 0.01; ***, P < 0.001, vs. bulk cells. d Kaplan–Meier analysis showed that high levels of LC3/ALDH1 were significantly associated with poor OS (P = 0.046) and DFS (P = 0.008)