P-glycoprotein (P-gp; also known as MDR1 and ABCB1), the most extensively studied ABC member, actively pumps out a wide range of chemotherapeutics (e.g., doxorubicin (DOX), paclitaxel, vincristine) out of tumor cells, thereby reducing their therapeutic efficacy [5,6] and, thus, is considered as a valuable pharmacological target for overcoming MDR [7,8,9]. This evidence concerns the gene ABCB1 and neoplasm.