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

Figure 4

Combination treatment with PAC and ATRA increases intracellular Ca²⁺ level in a RAR/RXR-dependent manner. (a) WT 9-7 cells were treated with different agents for 72 h. (b) WT 9-7 cells were treated with DMSO or 10 nM ATRA plus 1 nM PAC for different time periods as indicated. The cells were then collected, and the intracellular Ca²⁺ levels were examined by flow cytometry. (c) WT 9-7 cells were treated with DMSO or 10 nM ATRA plus 1 nM PAC for 72 h, and the intracellular Ca²⁺ level in ADPKD cells was visualized by fluorescence microscopy (200x, scale bar indicates 100 μm). (d) WT 9-7 cells were treated with 1 nM PAC and 100 nM RAR or RXR agonist for 72 h. (e) Cells were then incubated with 1 nM PAC and 10 nM ATRA in the presence of 100 nM RAR or RXR antagonist for 72 h. Cells were collected, and the intracellular Ca²⁺ level was measured by flow cytometry. vs. DMSO, ^#. (f) WT 9-7 cells were treated with DMSO or 1 nM PAC plus 10 nM ATRA in the presence of calcium channel blockers 1 μM BTP-2 and 20 μM verapamil for 72 h. Cells were then collected, and the intracellular Ca²⁺ level was measured by flow cytometry. vs. DMSO, , ^#.

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