P-glycoprotein is a transmembrane protein that actively transports a wide variety of substances out of cells. In cancer therapy, P-gp can reduce the efficacy of chemotherapeutic agents by pumping them out of cancer cells, leading to multidrug resistance (MDR). Tariquidar works by inhibiting the action of P-gp, allowing higher concentrations of chemotherapeutic drugs to remain inside cancer cells, thereby enhancing their cytotoxic effects.
