BPR0L075 induces PARP cleavage and DNA fragmentation in parental cells, but not in the paclitaxel-resistant ovarian cancer cells.

<p>Western blot analysis of the PARP, caspase-2, and caspase-3 after BPR0L075 (10–100 nM) treatment for 24 hours in the OVCAR-3/OVCAR-3-TR cells (A) and SKOV-3/SKOV-3-TR cells (B). β-actin was loading control. (C) DNA ladder assays in cells treated with 10 nM BPR0L075 for 72 hours. Genomic DNA was subjected to 1% agarose gel electrophoresis. The gel was stained with ethidium bromide and the DNA bands were visualized under an ultraviolet transilluminator. (D) Effect of caspase-3 inhibitor on BPR0L075 induced cytotoxicity. Cells were pretreated with caspase-3 inhibitor (20 µM Z-DEVD-FMK) or negative control inhibitor (20 µM Z-FA-FMK) for 24 hours before incubation with 10 nM BPR0L075 for additional 72 hours. On completion of the incubation, the cell viability was determined by SRB assay. No statistically significant difference of cytotoxicity was observed for each pair of cell lines (<i>P</i>>0.05, student <i>t</i>-test). Data represent mean ± SD.