Among them, ATP-binding cassette (ABC) transporter proteins such as MDR1,Breast cancer resistance protein (BCRP), and Multi-drug resistant associate protein 1(MRP1) are recognized molecules that promote the development of MDR [19] and can play an important role in gemcitabine chemoresistance in pancreatic cancer patients [20]. The gene discussed is ABCG2; the disease is pancreatic neoplasm.