N-ras and human cancer.

Activated N-ras genes have been detected in a variety of human tumours and tumour derived cell lines. It has been proposed that mutation or amplification of an N-ras gene represents one of the key steps in the development of some human tumours. Here we discuss the various methods by which activated N-ras genes have been detected, the ways in which they have become activated, and their contributions to the transformed phenotype.