Synergistic Therapy of Doxorubicin with Cationic Anticancer Peptide L-K6 Reverses Multidrug Resistance in MCF-7/ADR Cancer Cells In Vitro via P-glycoprotein Inhibition

Multidrug resistance (MDR) is one of the major obstacles to efficient chemotherapy against cancers, resulting from overexpression drug efflux transporters such as P-glycoprotein (P-gP). In present study, we aimed evaluate MDR reversal activity and synergistic therapeutic potential cationic anticancer peptide L-K6 with doxorubicin (DOX) on P-gP-overexpressing DOX-resistant MCF-7/ADR human breast cancer cells. Flow cytometry confocal laser scanning microscopy were used determine intracellular accumulation DOX another P-gP substrate, Rho123. P-gP-Glo assay, Western blot Biacore analysis further performed function expression. The cytotoxicity in MCF-7 or cells was measured by MTT assay. assay observation clearly revealed an increased Rho123 treated L-K6, suggesting a inhibiting potential. analysis, confirmed that could directly interact P-gP, inhibit decrease expression addition, expected, data indicated restored sensitivity DOX, indicating promising activity. All these findings may provide experimental evidence support applications peptidic inhibitors cancer.