Metastatic heterogeneity of cells from an ultraviolet light-induced murine fibrosarcoma of recent origin
Kripke, M.L.; Gruys, E.; Fidler, I.J.
Cancer Research 38(9): 2962-2967
1978
ISSN/ISBN: 0008-5472 PMID: 679204 Document Number: 128026
It was determined whether cells within a murine tumor of recent origin vary in their metastatic potential. A fibrosarcoma induced in a C3H- mouse by chronic UV irradiation was established in tissue culture, and 21 clones were produced from the parent line. For determination of whether cells with different metastatic potential preexisted in the population or whether the process of metastasis resulted from the random survival of cells with equal metastatic capabilities, the parent line and 21 clones were tested for metastatic behavior in syngeneic mice. Three in vivo tests were used: Mice were given injections of 105 tumor cells i.v., they were killed 18 days later and the tumor colonies in the lungs were counted. Mice were given s.c. injections of 106 tumor cells and examined at death for the presence of spontaneous metastases. Mice were given i.v. injections of 106 tumor cells and autopsied at death. The time of death was recorded, and the number and site of metastases were determined. The clones varied in their ability to grow and metastasize after s.c. or i.v. inoculation. The 3 tests gave similar results in that clones judged to be of high or low metastatic potential in 1 test usually exhibited the same behavior in the other 2 tests. The parent tumor is heterogeneous and cells with different metastatic potential preexist in the parental population.