Vascular Endothelial Growth Factor Expression in Oral Epithelial Dysplasia and Oral Squamous Cell Carcinoma

Background: Among the molecular events involved in carcinogenesis, neovascularization or angiogenesis is considered to be crucial for tumor growth and progression. VEGF is an angiogenic cytokine involved in endothelial cell proliferation, migration and differentiation. Aim: The purpose of this study was to investigate the immunohistochemical expression of VEGF in normal oral mucosa (NOM), epithelial dysplasia and oral squamous cell carcinoma (OSCC) and to correlate this expression with histologic features of tumor progression. Materials and methods: In this retrospective study, we examined the immunohistochemical expression of VEGF in 46 oral mucosal biopsy samples which consisted of 5 normal oral mucosal specimens, 17 specimens with varying histologic degrees of epithelial dysplasia and 24 invasive OSCC specimens with varying grades of tumor differentiation. Results: Statistical analysis indicated an upregulation of VEGF during the transition from NOM through epithelial dysplasia to OSCC whereas a significant correlation could not be established between various grades of dysplasia. An increased and intense expression of VEGF was observed in different histologic grades of squamous cell carcinoma with well differentiated OSCC showing the lowest mean VEGF percentage and intensity scores and poorly differentiated OSCC, the highest. Conclusion: Our results suggest that VEGF is present in elevated levels in dysplasias and OSCCs when compared with normal oral mucosal specimens. Increased levels of this angiogenic factor could enhance tumor growth by promoting neovascularization.