Nm23: an invasion suppressor gene in CNS tumours?

The nm23 gene family is widely documented as a suppressor of the metastatic phenotype in many human cancers. However, its role with respect to the invasive behavior of primary central nervous system tumours has scarcely been addressed. This review describes the members of this family identified to date and outlines the in vitro and in vivo data gathered from nearly ten years of nm23 research within the context of malignant progression in peripheral tumours. It is clear that this is an area which can no longer be ignored by the brain tumor community. Human nm23 bears strong sequence homology to the awd gene in Drosophila, mutations in which cause abnormal morphology of larval neural tissue. The functions and possible mechanisms underlying the ability of nm23 to suppress metastatic behavior are discussed.