Vet Pathol Email Content Delivery
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
This Article
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Citing Articles
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Wakui, S.
Right arrow Articles by Ushigome, S.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Wakui, S.
Right arrow Articles by Ushigome, S.

Veterinary Pathology, Vol 36, Issue 2 111-116, Copyright © 1999 by American College of Veterinary Pathologists

ARTICLES

Expression of vascular endothelial growth factor in N-butyl-N-(4-hydroxybutyl)nitrosamine-induced rat bladder carcinogenesis

S. Wakui, M. Furusato, S. Sasaki, T. Muto, H. Takahashi, T. Masaoka and S. Ushigome
Comparative Toxicology Laboratories, School of Veterinary Medicine, Azabu University, Sagamihara, Kanagawa, Japan. wakui@azabu-u.ac.jp

Vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF) are proteins implicated in tumor-associated microvascular angiogenesis. Expressions of VEGF and bFGF in various stages of chemical-induced rat bladder carcinogenesis were immunohistochemically investigated. Thirty-two male 6-week-old Wistar rats were given drinking water containing 0.05% N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN) for 20 weeks. VEGF and bFGF were not detected in the normal bladder epithelium. In simple hyperplasia, intensive expression of VEGF was observed in a few epithelial cells, and the expression of epithelial VEGF became more pronounced in papillary or nodular (PN) hyperplasia and papilloma. In carcinoma, heterogeneous expression of VEGF was observed in focal tumor cells, intensely expressed in the invading tumor cells. Ultrastructurally, carcinoma cells showed VEGF immunoreactivity in the cytoplasmic matrix and some rough endoplasmic reticulum, and VEGF-positive and -negative carcinoma cells were also clearly defined. High levels of VEGF mRNA were observed in the carcinoma. However, bFGF was not detected in the epithelium throughout the carcinogenesis. Increased microvessel counts appeared at simple hyperplasia and became more pronounced in PN hyperplasia, papilloma, and carcinoma (F-test; P < 0.05). In the carcinoma, the microvessel counts of the VEGF-expressing tumor areas were significantly higher than that of the non-VEGF-expressing tumor areas (U-test; P < 0.05). The present study suggests that upregulation of epithelial VEGF may begin at a quite early stage in BBN-induced rat bladder carcinogenesis, but bFGF may not be involved.




HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Copyright © 1999 by the American College of Veterinary Pathologists.