Increasing the cisplatin cytotoxicity and cisplatin-induced DNA damage by conferone in 5637 cells.

Despite widespread application of cisplatin in treatment of transitional cell carcinomas, its efficiency is far from satisfactory due to acquired drug resistance. The present study was carried out to estimate the effects of conferone, a sesquiterpene-coumarin isolated from Ferula badrakema, on increasing cisplatin cytotoxicity in 5637 cells. In order to determine conferone effects, 5637 cells were cultured in the presence of different concentrations of conferone and cisplatin in combination. The cytotoxicity and DNA damaging effects were then studied using MTT and comet assays, respectively. The results revealed that 24 h after the combination of 1 µg mL⁻¹ cisplatin with 32 µg mL⁻¹ conferone, the cytotoxicity of cisplatin was increased by 36.76%, and comet assay analyses showed that conferone could enhance the DNA damaging effects of cisplatin by 41%.