Increased vascularization in the skin of VEGF-overexpressing mice after long-term UVB irradiation. Compared with their wild-type littermates (A), VEGF-overexpressing mice that did not undergo irradiation had a slight increase in cutaneous vascularization (B). No changes were observed in wild-type mice (C) after long-term UVB irradiation, but increased cutaneous vascularization, with prominent enlargement of blood vessels, was observed after chronic UVB treatment of the skin of VEGF-overexpressing mice (D). Scale bars, 3 mm. Images were taken using a Nikon Coolpix 950 digital camera.