Synergistic Antiproliferative Effects of All-Trans Retinoic Acid and Paclitaxel on Autosomal Dominant Polycystic Kidney Disease Epithelial Cells

Figure 3

Combination treatment with PAC and ATRA induces apoptosis by upregulating p53 and caspase-8 expression. WT 9-7 cells were treated with DMSO or 1 nM PAC and 10 nM ATRA for 48 h. (a) To observe the morphology of the nucleus, the cells were stained with Hoechst 33342. Photographs were taken under a fluorescence microscope (200x, scale bar indicates 100 μm). White arrows indicate fragmented nuclei, and red arrows represent multilobe nuclei. (b, c) To examine cellular apoptosis, cells were treated with 1 nM PAC and 10 nM ATRA for different time periods (upper panel for 48 h, middle panel for 72 h, and lower panel for 96 h) and then incubated with FITC-Annexin V in a buffer containing PI and analyzed by flow cytometry. vs. DMSO, ^#. (d) To determine the apoptosis mechanism, protein expression was examined by western blotting. WT 9-7 cells were treated with DMSO or 1 nM PAC plus 10 nM ATRA for 72 h. Cells were then collected and subjected to western blotting to detect p53, cyclin B1, caspase-3, caspase-8, and caspase-9 expression. (e) Densitometric analysis of protein bands was performed by ImageJ software. The band density of each protein was normalized against that of actin. .

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