Cucurbitacin D Induces G2/M Phase Arrest and Apoptosis via the ROS/p38 Pathway in Capan-1 Pancreatic Cancer Cell Line

Figure 5

Cucurbitacin D (CuD) activates p38/c-Jun signaling pathway via generation of reactive oxygen species (ROS): (a) Capan-1 cells were treated with CuD (0.05, 0.1, and 0.2 μM) for 24 h and activation of the p38 pathway was assessed via western blotting. The histograms indicate the relative protein expression. Results are shown as mean ± SD from three independent experiments. , significantly different as compared to the control (0 μM). (b) Cells were preincubated with N-acetyl-L-cysteine (NAC; 5 mM) for 1 h and then treated with CuD (0.1 µM) for 24 h. Western blotting was performed to identify the ROS-mediated p38 signaling pathway in Capan-1 cells. (c and d) Capan-1 cell line was preincubated with SB203580 (20 μM) for 1 h and then treated with CuD for 24 h. G2/M cell cycle arrest-related proteins and apoptosis-related proteins were analyzed by western blotting. (e) The schematic representation of the effects of CuD. CuD induces ROS generation, and then activates the p21 and p38 signaling pathways to induce G2/M cell cycle arrest and apoptosis, respectively.

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