Figure 6-4244.

Immunohistochemical analysis of Anx A2 expression in tumors and non-neoplastic ductal complexes. A–D: Anx A2 expression in tumors from Ela1-TAg and Ela1-myc transgenic mice. Sections of paraffin-embeded pancreatic tissues were analyzed for Anx A2 expression as described in Materials and Methods. Normal pancreatic tissue from wild-type mice (A and B); acinar tumor from a 5-month-old Ela1-TAg mouse (C); ductal component in a mixed acinar-ductal carcinoma from a 5-month-old Ela1-myc mouse (D). Pre-immune serum (A); anti-Anx A2 serum (B–D). Anx A2 shows an apical expression in normal ductal cells (inset, B) but it is undetectable in normal acinar cells (B) and in acinar tumors (C and inset). By contrast, tumor cells with a ductal phenotype show an increased and unpolarized expression of Anx A2 (D, also see inset). Anx A2 is also detected in stromal cells (B and C). E and F: Anx A2 expression in non-neoplastic ductal complexes from Ela1-myc (E) and MT-TGF-α (F). Anx A2 was expressed in non-neoplastic ductal complexes in both mouse models (insets). Original magnification; ×200 (A, B, inset in F), ×100 (C–F), ×400 (insets in B–E).