Expression of Basic Fibroblast Growth Factor, Vascular Endothelial Growth Factor, and Thrombospondin‐1 Related to Microvessel Density in Nonaggressive and Aggressive Basal Cell Carcinomas

The aggressive forms of basal cell carcinoma (BCC) are biologically different in a number of features from their nonaggressive counterparts. The expression of basic Fibroblast Growth Factor (bFGF), Vascular Endothelial Growth Factor (VEGF), and Thrombospondin‐1 (TSP‐1) was examined in primary culture samples of nonaggressive and aggressive BCCs. We studied the relationship between neoangiogenesis by counting microvessels, tumor aggressiveness, and the expression of three different angiogenic factors. bFGF mRNA was detectable in all BCC samples, but there was no significant difference in the levels of expression between the two types. VEGF mRNA was also detectable in all BCC samples. VEGF expression in the aggressive type was approximately 3.5‐fold higher than in the nonaggressive type. TSP‐1 expression was variable and not related to the type of BCC. The mean value of microvessel density (MVD) was significantly higher for the aggressive type than for the nonaggressive type. There was a significant correlation between VEGF levels and MVD. No significant relationships were found between bFGF, TSP‐1 mRNA expression, and MVD. In conclusion, the results of present study suggest that VEGF expression and angiogenesis might play important roles in the progression to aggressive BCC.