A schematic representation of PGF
-FP receptor signalling which differentially regulates endothelial network formation and proliferation. PGF2α-FP receptor signalling in epithelial cells promotes the release of FGF2 into culture medium (conditioned medium). Conditioned medium treatment of HUVECs promotes the activation of ERK1/2 signalling via the FGF2-FGFR1. ERK1/2 activates divergent signalling pathways to endothelial proliferation and network formation. Endothelial proliferation is activated via mTOR. Endothelial network formation is activated via the induction of endothelial COX-2 enhancing the biosynthesis and release of PGF2α. Endothelial PGF2α subsequently acts on endothelial FP receptors to promote network formation (endothelial differentiation).