Targeting key steps in metastatic tumour progression.

The key determinants of tumour progression and discriminators of benign and malignant lesions include neoangiogenesis (the induction of a new blood supply) and the capacity of malignant cells to invade and metastasise. It is now recognized that these processes can be co-ordinately regulated by the activity of specific genes -- often distinct from those involved in early oncogenesis -- and involve common signalling pathways. Cell motility and chemotaxis (the ability to respond to gradients of chemoattractants) are implicated in both tumour-cell invasion and response of activated endothelial cells to angiogenic cytokines, and provide interesting and novel points for therapeutic intervention.