Melanoma cell lines express VEGF receptor KDR and respond to exogenously added VEGF

Tumour-secreted vascular endothelial growth factor (VEGF) exerts a number of effects which are important in tumour pathology, including stimulation of angiogenesis and permeabilisation of tumour-associated vasculature. In this study we have examined the possibility that VEGF may also play an autocrine role in tumour growth. Using reverse-transcriptase polymerase chain reaction (RT-PCR), the expression of VEGF was found in 15/15 human tumour cell lines examined, while the VEGF receptor KDR was detected only in three melanoma cell lines (MeWo and A375, both wild type and metastatic variant). Exogenously added VEGF (10ng/ml) was able to stimulate up to 40% increased proliferation of A375 M melanoma cells following a 48-h period of quiescence, suggesting that VEGF may indeed play a role in autocrine, as well as paracrine, stimulation of melanoma growth.