Expression of the tumor metastatic suppressor gene in mouse melanoma model: inverse association to metastatic potential.

Data obtained in experimental cutaneous melanomas have suggested that the nm23 gene may function as a metastasis suppressor gene. The nm23 level in 8 human cutaneous melanoma cell lines and 2 murine melanoma cell lines were examined. Each melanoma cell line was transplanted subcutaneously into the flank of nude mice, and the metastatic behavior was evaluated by counting lung tumor foci and by determining host survival time. It was found that expression of nm23 mRNA in human melanomas is correlated closely with reduced metastatic behavior in experimental animals and may serve as a sensitive prognostic indicator of malignancy and survival in patients with melanomas.