High nuclear Ctnnb1 staining was also observed in infrequent, undifferentiated, Apcfl/fl;R26LSL-MYC end-stage tumours unlike the Ctnnb1ex3/WT;R26LSL-MYC tumours that maintained lower levels of nuclear Ctnnb1 (Fig. 5g). This evidence concerns the gene CTNNB1 and neoplasm.