Expression of Vascular Endothelial Growth Factor (VEGF) and its mRNA in Uterine Cervical Carcinomas

Yum, Yoon Seok; Lee, Seon Kyung; Chi, Sung Gil; Lee, Ju Hee; Kim, Seung Bo

Abstract

OBJECTIVE
Angiogenesis, the formation of blood vessels by sprouting from pre-existing ones, is essential for the growth of solid tumors beyond 2-3mm in diameter and for tumor metastasis. Vascular endothelial growth factor (VEGF), is known as vascular permeability factor(VPF) and mediates vascularization and tumor-induced angiogenesis. This study examined the potential of growth, invasion, and metastasis of uterine cervical carcinomas associated with neovascularization.
METHODS
From January 1996 to December 1999, at the Department of Obstetrics and Gynecology, Kyung-Hee University Hospital, 37 uterine cervical carcinomas and 7 normal cervical tissues were obtained and the samples were immediately frozen and stored at -70 degrees C. Immunohistochemical staining for VEGF was carried out to study VEGF localization, and the levels of VEGF subtype mRNAs were determined by quantitative RT-PCR in specimens. The relation between VEGF subtypes expression of cervical cancers was analysed.
RESULTS
The positive staining for VEGF is seen dominantly in the cytoplasm of the cancer cells, and faintly in interstitial cells. The intensity of staining was stronger in squamous carcinomas than in adenocrcinomas, but there was no significant difference (p>0.05). Quantitative RT-PCR analysis demonstrated significantly increased VEGF121/VEGF165 mRNA expression levels (>0.56 / >0.72) in 21 (56.8%) and 15 (40.5%) of 37 cervical carcinomas comparing to control groups (mean: 0.28 / 0.36). There was no obvious relationship between VEGF121/VEGF165 mRNA expression levels and the clinical parameters examined including age, pathology, differentiation, tumor size, lymphovascular space invasion, LN involvement and invasion depth except clinical stage (p<0.05).
CONCLUSIONS
The overexpression of VEGF mRNA may be an important contributing factor in cervical carcinomas. There is no significant differenece of VEGF mRNAs levels according to clinical parameters, so it seems that the expression of VEGF is involved in the promotion of angiogenesis on cervical cancer and plays an important role in early invasion.