Abstract B49: The role of oxidative stress in the development of cisplatin resistance in epithelial ovarian cancer

Abstract Objective: To investigate the role of oxidative stress in the development of cisplatin resistance in epithelial ovarian cancer (EOC). Methods: Two parent EOC cell lines (MDAH-2774 and SKOV-3) and their chemoresistant counterparts were used. Total RNA was extracted and subjected to real-time RT-PCR to evaluate the expression of inducible nitric oxide synthase (iNOS) and glutathione reductase (GSR) in all cells. Nitrate/nitrite levels and GSR activity were also measured using colorimetric and ELISA assays respectively. Cell proliferation was assessed using Ki-67 immunostaining in all cells. Unpaired t-tests were used for statistical analysis at p-value <0.05 for significance. Results: Both EOC cisplatin sensitive cells manifested significant increase in the expression and activity of GSR as compared to their resistant counterparts (p<0.05). On the other hand, EOC sensitive cells manifested a decrease in iNOS expression as compared to their resistant counterparts (p<0.05). Nitrate/nitrite levels were significantly decreased in EOC sensitive cells as compared to their resistant counterparts (p<0.05). Ki-67 immunofluorescence staining revealed increased proliferation in cisplatin resistant cells compared to controls for the MDAH-277a and SKOV-3 cell lines. Conclusion: Our data suggests that the development of cisplatin resistance heighten the prooxidant state in EOC leading to a further increase in cell proliferation. Citation Format: Jimmy Belotte, Nicole Fletcher, Awoniyi Awonuga, Mitchell Alexis, Husam Abu-soud, Michael Diamond, Mohammed Saed, Ghassan Saed. The role of oxidative stress in the development of cisplatin resistance in epithelial ovarian cancer. [abstract]. In: Proceedings of the AACR Special Conference on Advances in Ovarian Cancer Research: From Concept to Clinic; Sep 18-21, 2013; Miami, FL. Philadelphia (PA): AACR; Clin Cancer Res 2013;19(19 Suppl):Abstract nr B49.