Fig. 1

PD induces cell cycle arrest at G2/M phase and mitochondrial apoptosis in PAC cells. The viability of PAC cells (A, B) after PD treatment at concentrations of 0, 75, 100, 150 and 200 μg/mL was determined using CCK-8 for 24 h, 48 h and 72 h, respectively. Representative images of cell cycle distribution of PAC cells (C, D) after treated with PD (0–200 μg/mL) for 12–48 h, respectively. Quantification data of cell cycle distribution for PAC cells (E, F) are presented. The levels of G2/M phase-related regulatory proteins (p-CDC25C (Ser216), CDC25C, Cyclin B1, p-CDK1(Tyr15), CDK1 and p-Histone H3 (Ser10)) in PAC cells (G, H) were analyzed using immunoblotting following exposure to PD at concentrations of 0, 50, 100 and 200 μg/mL for 12 h. The expression levels were normalized to GAPDH. Double staining with Annexin V-FITC and PI was conducted to evaluate apoptosis in PAC cells (I, J) following PD treatment for 48 h (0–200 μg/mL) and then quantified (right panel). Apoptosis-associated protein expression was determined using immunoblotting in MIA PaCa-2 (K, L) and BxPC-3 (M, N) following PD treatment at concentrations of 0, 50, 100 and 200 μg/mL for duration of 12, 24 and 48 h. The expression levels were normalized to β-actin. 0.5 μM of GEM was chosen as the positive control. Results are presented as mean ± S.D. of triplicate independent experiments. *p < 0.05, **p < 0.01, ***p < 0.001 compared with the control