Tie receptors: New modulators of angiogenic and lymphangiogenic responses

Angiogenesis is required for normal embryonic vascular development and aber rant angiogenesis contributes to several diseases, including cancer; diabet es and tissue ischaemia. What are the molecular mechanisms that regulate th is important process? The Tie family of receptors and their ligands, the an giopoietins, are beginning to provide insight into how vessels make decisio ns such as whether to grow or regress - processes that are important not on ly during development but throughout an organism's life.