“…Accumulation research implied that ABC transporters may play a key role on the gemcitabine resistance in pancreatic cancer [6,11,12,23]. Ko143 is a widely reported inhibitor of breast cancer resistance protein (BCRP/ABCG2) [42] and significantly enhanced the sensitivity of PANC-1-R cells to gemcitabine by increasing drug efflux [43]. And verapamil, an ABCB1 inhibitor, resensitized the resistant cells to gemcitabine in a dose-dependent manner by promoting intracellular drug accumulation to combat chemotherapeutic resistance [44,45].…”