VEGFA and melanoma: The sVEGFR1 isoforms, sVEGFR1-i13, sVEGFR1-i14, sVEGFR1-e15a, and sVEGFR1-e15b (Fig. 3b), arise from alternative splicing and retain VEGF-binding capacity without downstream signaling.105 Produced by various cells, including endothelial and melanoma cells, sVEGFR1 often circulates bound to VEGF, playing a key role in regulating angiogenesis, particularly in pathological states such as pre-eclampsia.106