Reversal of paclitaxel resistance in epithelial ovarian carcinoma cells by a MUC1 aptamer-let-7i chimera.

The purpose of this study was to establish tumor tissue specific delivery of let-7i miRNA to reverse paclitaxel-induced chemoresistance. A chimera that combines MUC1 aptamer and let-7i miRNA was tested in OVCAR-3 ovarian cancer cells. Results demonstrated that the chimera can specifically be delivered into OVCAR-3 cells and the released let-7i significantly sensitized the role of paclitaxel in inhibiting cell proliferation, inducing cell apoptosis, and decreasing long-term cell survival. The chimera achieved reversal of chemoresistance through downregulation of cyclin D1, cyclin D2, Dicer 1, and PGRMC1 expressions. Our study indicated that this MUC1/let-7i chimera can specifically reverse chemoresistance to paclitaxel.