“First, we found that GBD could decrease the half maximal inhibitory concentration of paclitaxel and doxorubicin (DOX) in breast cancer cells like MDA‐MB‐231/MDR1 cells and MCF‐7/ADR cells.”
“In …, GBD can increase the accumulation of DOX in MDA‐MB‐231/MDR1 cells by suppressing the expression of P‐gp and competitively inhibiting the P‐gp efflux pump and enhance the apoptosis of MDA‐MB‐231/MDR1 cells induced by DOX, and thus realize reversal effects on MDR.”
“It was further explained that GBD enhanced the apoptosis of MDA‐MB‐231/MDR1 cells induced by DOX , due to the increased accumulation of DOX.”
“On the other hand, GBD can downregulate the activity of P‐gp ATPase when cotreated with DOX or verapamil, revealing that GBD was a substrate of P‐gp.”