Expression of VEGF-receptors on Uveal Melanoma

Abstract

Abstract: : Purpose: To evaluate the possible role of different members of the Vascular Endothelial Growth Factor (VEGF)-family on the growth and vascularisation of the uveal melanoma, the three VEGF-receptors were evaluated. Methods: Fresh frozen tissue of 40 uveal melanoma was evaluated for VEGF-R1 (Flt1), VEGF-R2 (KDR) and VEGF-R3 (Flt4) by immunohistochemistry with monoclonal antibodies. Endothelial cells were stained with PAL-E and CD31. The tumor tissue was also analyzed by RT-PCR. Results: The three VEGF-receptors were expressed on the uveal melanoma slides. The staining for VEGF-R3 was the most profound. Endothelial cells were stained for VEGF-R1 in 31/40 (77.5%) tumors, VEGF-R2 in 33/40 (82.5%) and VEGF-R3 (87.5%). No correlation could be found between expression of VEGF-receptors and microvascular density or PAS patterns. PAL-E and CD31 was expressed in all tumors. Conclusions: VEGF-R1, -R2 and VEGF-R3 are expressed on endothelial cells in uveal melanoma. This indicates a potential important role for several members of the VEGF-family in regulating angiogenesis in uveal melanoma.

Keywords: melanoma • growth factors/growth factor receptors • oncology