ABSTRACT
In ligh t o f th is largely p relim inary know ledge o u r review sum m arizes da ta o n cellular and m olecu lar m echanism s underly ing th e p h en o ty p ic characteristics o f tu m o r cells th a t d e ter m in e th e ir invasive capability. F u rth e r aspects o f m etastasis, i.e., angiogenesis, will n o t be considered here.
