FOLR1 and neoplasm: KPCY2838c3 pancreatic ductal adenocarcinoma cells derived from KPCY mice were engineered to express human FRα antigen and Luc2 (FRα+Luc2+KPCY cells) for assessing tumor growth, and 0.5 × 106 were intraperitoneally (i.p.)implanted in NSG mice.