Tumorigenicity was compared between NOG-EGFP mice and NOD/SCID mice using the pancreato-biliary cancer cell lines. A) TFK-1, B) HuCCT1, C) MIAPaCa2 and D) AsPC-1. A total of 5.0 × 105 cells was injected into each mouse (n = 6). ** denotes P < 0.01. NOG-EGFP mice showed a significantly higher tumorigenic potential than that of NOD/SCID mice in all cell lines ( p < 0.01).