Kumamoto Hiroyuki, Ohki Kousuke, Ooya Kiyoshi
Division of Oral Pathology, Department of Oral Medicine and Bioregulation, Tohoku University Graduate School of Dentistry, Sendai, Japan.
J Oral Pathol Med. 2002 Jan;31(1):28-34. doi: 10.1046/j.0904-2512.2001.10061.x.
Expression of vascular endothelial growth factor (VEGF), a major angiogenic factor, and microvessel density (MVD), assessed by the use of anti-CD34 antibody, were immunohistochemically examined in benign and malignant ameloblastomas, as well as tooth germs, to clarify the possible role of angiogenesis in epithelial odontogenic tumors.
Specimens of 5 tooth germs, 35 benign ameloblastomas and 5 malignant ameloblastomas were examined by immunohistochemistry using anti-VEGF and CD34 monoclonal antibodies.
Immunoreactivity for VEGF was detected in both normal and neoplastic odontogenic epithelial cells, and weakly in microvessels near odontogenic epithelial cells, suggesting that this angiogenic factor acts on endothelial cells via a paracrine mechanism in odontogenic tissues. Both benign and malignant ameloblastomas showed elevated VEGF expression as compared to tooth germs. VEGF expression was low in keratinizing cells in acanthomatous ameloblastomas and granular cells in granular cell ameloblastomas, and acanthomatous ameloblastomas showed the lowest VEGF reactivity among the subtypes of ameloblastomas. MVD in both benign and malignant ameloblastomas was higher than that in tooth germs, indicating increased demands for blood in the neoplastic tissues. CD34-positive microvessels in follicular ameloblastomas were numerous and small, whereas those in plexiform ameloblastomas were scattered and dilated. MVD tended to depend on VEGF expression levels in both benign and malignant ameloblastomas.
VEGF was considered to be an important mediator of angiogenesis in these epithelial odontogenic tumors, and up-regulation of VEGF might be associated with neoplastic or malignant changes of odontogenic epithelial cells.
血管内皮生长因子（VEGF）是一种主要的血管生成因子，通过使用抗CD34抗体评估的微血管密度（MVD），在良性和恶性成釉细胞瘤以及牙胚中进行了免疫组织化学检查，以阐明血管生成在牙源性上皮肿瘤中的可能作用。
使用抗VEGF和CD34单克隆抗体，通过免疫组织化学检查5个牙胚、35个良性成釉细胞瘤和5个恶性成釉细胞瘤的标本。
在正常和肿瘤性牙源性上皮细胞中均检测到VEGF的免疫反应性，在牙源性上皮细胞附近的微血管中反应较弱，表明这种血管生成因子在牙源性组织中通过旁分泌机制作用于内皮细胞。与牙胚相比，良性和恶性成釉细胞瘤均显示VEGF表达升高。棘皮瘤型成釉细胞瘤中的角化细胞和颗粒细胞型成釉细胞瘤中的颗粒细胞VEGF表达较低，并且棘皮瘤型成釉细胞瘤在成釉细胞瘤亚型中显示出最低的VEGF反应性。良性和恶性成釉细胞瘤中的MVD均高于牙胚中的MVD，表明肿瘤组织对血液的需求增加。滤泡型成釉细胞瘤中的CD34阳性微血管数量众多且细小，而丛状型成釉细胞瘤中的则分散且扩张。在良性和恶性成釉细胞瘤中，MVD倾向于依赖VEGF表达水平。
VEGF被认为是这些牙源性上皮肿瘤中血管生成的重要介质，VEGF的上调可能与牙源性上皮细胞的肿瘤性或恶性变化有关。
