Fig. 3. Pancreatomegaly is c-myc dependent. (A) Freshly dissected pancreata from 2-month-old Apc^P-/- and Apc^P-/-;c-myc^P-/- mice. Pancreatomegaly does not appear in the absence of the two c-myc alleles. (B) Anti-ß-catenin immunofluorescence on 2-month-old Apc^P-/- and Apc^P-/-;c-myc^P-/- pancreatic sections. Notice the nuclear localization of ß-catenin in acinar cells of mice of both genotypes (open arrows). Islets are depicted with a dashed line. Paraffin sections were 5 µm thick. Small arrows show cytoplasmic ß-catenin in islets and ducts (d). (C) Western blot of total protein extracts from adult pancreas (50 µg per lane) using anti-unphosphorylated ß-catenin antibody. Unphosphorylated ß-catenin accumulates in the pancreas of Apc^P-/-;c-myc^P-/- mice, as in Apc^P-/- animals. ß-tubulin shows equal loading. (D) ß-cell area in Apc^P-/-;c-myc^P-/- mice is similar to that of controls, whereas it is lower in Apc^P-/- animals. A total of three mice were analyzed per group; ^*P<0.01. d, duodenum (A), duct (B); p, pancreas; sp, spleen. Scale bar: 0.5 cm in A; 20 µm in B.