title: Expression of vascular endothelial growth factor and presence of angiovascular cells in tissues from different thyroid disorders.
abstract: BACKGROUND
  Vascular endothelial growth factor (VEGF) is involved in tumor angiogenesis and other pathophysiological processes.
  
  
  METHODS
  We studied the localization of VEGF in human thyroid tissues to clarify its involvement in proliferative processes in a variety of thyroid disorders. Immunohistochemical analysis using purified rabbit polyclonal anti-human VEGF or anti-human CD34 antibody and a streptavidin-biotin peroxidase complex detection system was performed on 58 tissue specimens from 53 patients with different thyroid disorders and 5 normal thyroid glands.
  
  
  RESULTS
  Vascular endothelial growth factor was not detected in normal thyroid follicular cells. However, some thyroid tumor cells expressed VEGF in the cytoplasm (papillary carcinoma, 10/18; follicular carcinoma, 1/3; medullary carcinoma, 2/2; follicular adenoma, 3/11; adenomatous goiter, 2/4). In benign follicular adenoma and adenomatous goiter, weak expression of VEGF was found in small areas of the tumor, whereas in malignant thyroid tumors, it was strongly expressed in many cells. However, VEGF was not expressed in anaplastic carcinoma, malignant lymphoma, or Graves' disease. Angiovascular cells stained with CD34 antibody in tissues from different thyroid disorders reflected statistically significant differences in papillary carcinoma, follicular adenoma, and Graves' disease compared with normal thyroids, and such cells showed a trend toward increases in medullary carcinoma and adenomatous goiter. In contrast, low vascularity was observed in anaplastic carcinoma, malignant lymphoma, and follicular carcinoma.
  
  
  CONCLUSIONS
  Because VEGF probably functions as a hypoxia-inducible angiogenic factor, overexpression of this mediator, concomitant with hypervascularity, may be induced more strongly in malignant thyroid tumors, which need more oxygen to proliferate, than in benign follicular tumors. However, neither VEGF nor CD34 was expressed in anaplastic thyroid carcinoma, which is an extremely poorly differentiated malignant tumor. CD34 but not VEGF was expressed in the hyperplastic thyroid tissues of Graves' disease composed of nontransformed cells. Thus, the expression of VEGF concomitant with CD34 is suggested to reflect both the transformation and differentiation state of malignant tumors.
authors.affiliation: Department of Surgery, Fujita Health University School of Medicine, Toyoake, Aichi, 470-1192, Japan.
authors.forename: Asako
authors.initials: A
authors.lastname: Itoh
authors.forename: Katsumi
authors.initials: K
authors.lastname: Iwase
authors.forename: Shin
authors.initials: S
authors.lastname: Jimbo
authors.forename: Haruo
authors.initials: H
authors.lastname: Yamamoto
authors.forename: Naoki
authors.initials: N
authors.lastname: Yamamoto
authors.forename: Masahiro
authors.initials: M
authors.lastname: Kokubo
authors.forename: Takao
authors.initials: T
authors.lastname: Senda
authors.forename: Akira
authors.initials: A
authors.lastname: Nakai
authors.forename: Akio
authors.initials: A
authors.lastname: Nagagasaka
authors.forename: Takaaki
authors.initials: T
authors.lastname: Nagasaka
authors.forename: Yatsuka
authors.initials: Y
authors.lastname: Hibi
authors.forename: Teppei
authors.initials: T
authors.lastname: Seko
mesh_terms: D000328:Adult; D005260:Female; D006801:Humans; D007124:Immunoenzyme Techniques; D008297:Male; D009389:Neovascularization, Pathologic / Q000378:metabolism* / Q000503:physiopathology; D013959:Thyroid Diseases / Q000378:metabolism* / Q000503:physiopathology; D013961:Thyroid Gland / Q000166:cytology / Q000378:metabolism; D042461:Vascular Endothelial Growth Factor A / Q000378:metabolism*
chemical_list: D042461:Vascular Endothelial Growth Factor A