Journal List > Korean J Obstet Gynecol > v.54(2) > 1088388




The objectives of this study were to determine the efficacy of NV-196, a synthetic isoflavone derivative, as a chemosensitizer in chemoresistant CP70 and R182 epithelial ovarian cancer (EOC) cells and to characterize the mechanism behind its sensitizing effect.


EOC cells were treated with tenfold dilutions of NV-196 (0.1 to 10 μg/mL) for 24 and 48 hours. Cell viability was determined by the CellTiter 96 AQueous One Solution Cell Proliferation Assay. Apoptosis was assessed by Caspase-Glo assays and apoptotic cascade X-linked inhibitor of apoptosis protein (XIAP), caspase-2 and Bid were characterized by Western blot analyses.


As a monotherapy, NV-196 showed decreased cell viability in a time- and dose-dependent manner in both CP70 and R182 cells. A significant increase in caspase-3 activity was observed in both cells. Caspase-8 and -9 activation were also observed. Western blots demonstrated Bid and caspase-2 activation and cleavage of XIAP. NV-196 enhances the cytotoxic effects of carboplatin and paclitaxel.


NV-196 induces cell death through the induction of apoptosis. Pretreatment with NV-196 may sensitize the ovarian cancer cells to carboplatin or paclitaxel. NV-196 may act as a chemosensitizing agent in epithelial ovarian cancer cells.


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Fig. 1.
(A, B) NV-196 decreases the viability of epithelial ovarian cancer (EOC) cells (CP70 and R182). The viability (in percentage, normalized to untreated cells) of EOC cells after treatment with increasing concentration of NV-196 for 24 and 48 hours. Data were compiled from at least three independent experiments, each done in triplicate (∗p<0.05). (C, D) CP70 and R182 cells were pretreated with 10 μg/mL NV-196 for 8 hours and then treated with carboplatin or paclitaxel for 24 hours. Cell viability was determined by the CellTiter 96 AQueous One Solution Cell Proliferation Assay (∗p<0.05).
Fig. 2.
(A) Phase-contrast images of NV-196 induced apoptosis in CP70 and R182 cells (×200). Both cells were treated with 10 μg/mL NV-196 for 24 and 48 hours. (B) Hoechst dye staining of apoptotic nuclei (×400), (a) non-treated control, (b) NV-196 treated CP70 cells, 10 μg/mL, 24 hours. NT: non-treated control.
Fig. 3.
Relative caspase-3, -8, -9 activity in CP70 and R182 cells. Cells were exposed to 10 μg/mL NV-196 for 12, 24, 36 and 48 hours. Caspase activity was measured by Caspase-Glo assays as described in Materials and Methods. Y axis: caspase activity fold increase from control. The data were compiled from at least three independent experiments (∗p<0.05).
Fig. 4.
Characterization of the apoptotic cascade induced by NV‐196. Western blot analyses showing the activation status of anti‐apoptotic protein and pro‐apop-totic protein after treatment with 10 μg/mL NV‐196 for 12, 24, 36, and 48 hours. Results for CP70 and R182 cells are shown.
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