Figure 5

Angiogenesis-associated homeobox proteins immunolabeled in canine normal ECs, original HSAs, and xenograft HSA tumors. Representative immunohistochemical results of HoxD3 and Pbx1 in active and quiescent ECs during angiogenesis. In granulation tissue, although immunoreactivity for HoxD3 (A) and Pbx1 (C) was localized in the nuclei and cytoplasm of angiogenic ECs, it was weak for HoxD3 in the nuclei. Immunoreactivity for HoxD3 (B) was not detected in quiescent ECs but for Pbx1 (D), the immunoreactivity was localized in the nuclei and cytoplasm of quiescent ECs. Representative immunohistochemical results of HoxA9, HoxB3, HoxB7, HoxD3, Pbx1, and Meis1 in original HSAs and xenograft HSA tumors. In all original HSAs, immunoreactivity for HoxA9 (E: the original tumor of Ud), HoxB3 (G: the original tumor of Sy), HoxD3 (K: the original tumor of Sa), Pbx1 (M: the original tumor of Ud), and Meis1 (O: the original tumor of Ud) was localized in the nuclei and cytoplasm of the neoplastic cells. HoxB7 (I: the original tumor of Sa) immunoreactivity was only localized in the nuclei of the neoplastic cells. Immunoreactivity for HoxA9 (F: Ud), HoxB3 (H: Sy), HoxB7 (J: Sa), HoxD3 (L: Sa), Pbx1 (N: Ud), and Meis1 (P: Ud) in all xenograft HSA tumors was detected in the same location as those original tumors. IHC; bars: 25 μm (A--D) and 50 μm (E--P).