Knock-down of Superoxide Dismutase 1 Sensitizes Cisplatin-resistant Human Ovarian Cancer Cells

Background: Overexpression of superoxide dismutase 1 (SOD1) has been shown to be one of the factors involved in causing cisplatin resistance in ovarian cancer. Reduction of SOD1 expression is expected to restore, at least partially, cisplatin sensitivity in ovarian cancer chemotherapy. Here, we explored the potential of RNAi as a therapy for reversal of cisplatin resistance. Materials and Methods: SOD1-specific small-interfering RNA (siRNA) was synthesized and transfected into cisplatin-resistant cell line A2780/CP prior to treatment with 15 mu M cisplatin. Cell survival was assessed by clonogenic assay. Results: An enhanced cisplatin sensitivity was observed in the A2780/CP cells treated with SOD1-specific siRNA, compared to non-siRNA-treated or scrambled-siRNA-treated control cells. Conclusion: Specifically targeting SOD1 could lead to sensitization of cisplatin-resistant ovarian cancer cells, and SOD1 may be used as a potential target for chemosensitizers.