Previous investigations on glomeruloid bodies (GB) have focused on the action of VEGF. Recently it has come to light that VEGF alone in insufficient for tumour angiogenesis but involves a host of other factors. The Tie-2 receptor tyrosine kinase has been identified as the only other endothelium specific receptor and is activated through angiopoetin-1 (Ang-1). Tie-2 activation is shown to increase vessel branching, increased interaction of vessel tissue within itself and its surroundings and endothelial survival. …
