Immunohistochemically Detection of Angiogenesis in Oral Pre-Cancerous Lesions Compared with Oral Invasive Carcinomas

Abstract

Background: Angiogenic activity is an important event in oral carcinogenesis. During transition of normal oral mucosa to different grades of dysplasia and to invasive carcinoma, significant increase of vascularity occurs. Angiogenesis can be determined by immunohistochemical assessment of several endothelial cell markers like Endogelin (CD 105), expressed in activated endothelial cells and associated with neovasculature, and the vascular endothelial growth factor (VEGF). This study was conducted to evaluate angiogenic activity in oral precancerous lesions compared with oral invasive carcinomas by immunohistochemical staining of VEGF and CD 105 proteins. Methods: In the present cross-sectional study, 20 normal, 20 pre-cancerous mucosa and 20 oral invasive carcinoma samples were immunohistochemically stained. Positive cells were counted in each section and micro vessel density (MVD) was determined. The data were statistically analyzed by Mann-Whitney and Kruskal-Wallis tests, with a P-value </=0.05 considered significant. Results: The mean expression value for VEGF was 24.6 in oral invasive carcinoma, 16.4 in precancerous mucosa and 15.5 in normal mucosa, with no significant differences between the latter two. Endoglin was negative in all normal mucosa samples, but had scores of 7.58 for precancerous mucosa and 19.4 in oral invasive carcinoma specimens. MVD was significantly higher in SCC than in dysplastic mucosa. Conclusion: Oral invasive carcinoma has more angiogenic activity in comparison with pre-cancerous lesions and normal mucosa. Given the high expression of CD105 positive vessels in malignant lesions, we can argue that determination of mean vessel density (MVD) by application of the CD105 marker could be a useful parameter to differentiate cancerous from pre-cancerous lesions.