To test whether the Wnt pathway was activated in irradiated tumor cells and its role in tumor repopulation, a 8×TopFlash luciferase reporter containing the wild-type LEF/TCF-binding site and a 8×FopFlash luciferase reporter containing a mutated LEF/TCF-binding site were stably transduced in Panc1 and HT29 cells. Here, HNF4A is linked to neoplasm.