VEGF expression in skin warts. Relevance to angiogenesis and vasodilation

Verrucae vulgaris (skin warts) are benign proliferative lesions which are g enerally associated with human papillomavirus type 2 (HPV-2) infection. Vas cular endothelial growth factor (VEGF) is an endothelial cell-specific mito gen able to induce angiogenesis and vasodilation, Our previous findings ind icate that these two processes take place during the formation of skin wart s. The purpose of this study was to determine whether VEGF expression in th ese lesions was associated with HPV infection, angiogenesis or vasodilation , To this end, paraffin-embedded specimens of skin warts which were either negative for HPV-1, -2, -3 and -4 (HPV-; n = 18), or positive for HPV-2 (HP V+; n = 21) were compared with histologically normal perilesional skin (n = 13), Serial sections were stained with antibodies to von Willebrand Factor (VWF) and to VEGF. Vascularity was quantified by point counting vWF-positi ve blood vessels. Small and large vessels were quantified separately, using a cut-off value of 50 mum diameter. VEGF expression in the epidermis was e stimated by consensus of two independent observers according to three indic es: (1) percentage of cells stained, (2) intensity of the staining, and (3) product of area and intensity (final score). Results were analysed by nonp arametric tests. Similar levels of VEGF were found in specimens of normal s kin, HPV- and HPV+ warts, irrespective of the index used. There was no sign ificant correlation between VEGF expression and vascularity values for eith er small or large vessels. These results indicate that, on its own, VEGF ex pression is not associated with angiogenesis, vasodilation or HPV infection in skin warts. The presence of VEGF in normal skin suggests that it may pl ay a role in tissue homeostasis.