Comparative evaluation of small-molecule chemosensitizers in reversal of cisplatin resistance in ovarian cancer cells.

Cisplatin-resistance is one of the major challenges in the treatment of epithelial ovarian cancer. Small-molecule chemosensitizers provide a therapeutically feasible approach to overcome cisplatin resistance in ovarian cancer. However, proper selection of chemosensitizer is of prime importance owing to phenotypic differences in cisplatin-resistant ovarian cancers. The resistance reversal activity of chemosensitizers buthionine sulfoximine (BSO), triethylenetetramine (TETA), genistein, rapamycin and colchicine was investigated in various cisplatin-resistant ovarian cancer cells, 2008 C13, CP70 and OVCAR 8 using MTT assays. Cellular accumulation of cisplatin in the presence of chemosensitizers was analyzed by inductively-coupled plasma-mass spectroscopy (ICP-MS). Chemosensitizers exhibited resistance reversal activity in 2008 C13 and CP70 cells in the following order; colchicine> genistein>TETA> rapamycin ≥ BSO (p<0.05), which is in correlation with cellular accumulation of cisplatin. In conclusion, our study demonstrates that resistance reversal activity of chemosensitizers varies with phenotypic behavior of cisplatin-resistant ovarian cancer cells. Data from our study can be utilized to choose a specific chemosensitizer for individualized combination therapy for cisplatin-resistant ovarian cancer.