Establishment of highly metastatic clones without tumorigenicity derived from Dunn osteosarcoma.

Thirteen clones were established from a Dunn osteosarcoma by means of limiting dilution. The heterogeneity of four parameters (in vivo and in vitro growth rates, alkaline phosphatase activity and metastatic capacity) was clearly demonstrated. Statistical analysis does not reveal a high correlation between the four parameters. The highly metastatic clones 5 and 10 lost tumorigenicity at the primary site. The presence of these clones suggests that the microenvironment of the host is able to control tumor growth and that metastasis should be considered as a differentiated phenotype in tumor progression.