Establishment and characterization of a subline predisposed to pulmonary metastasis from a human gestational choriocarcinoma cell line in nude mice.

A subline predisposed to pulmonary metastasis was successfully derived by repeating in vivo selection of GCH-1, a human gestational choriocarcinoma cell line, in nude mice. While the parent line GCH-1, transplanted subcutaneously to nude mice, induced pulmonary metastasis in a few of the host animals, the newly established subline GCH-1(m) successfully metastasized to the lungs in 100% of them. Compared with GCH-1, GCH-1(m) exhibited a higher degree of cell atypia, a lower capacity for cell growth and markedly higher productivity for human chorionic gonadotropin (hCG). Another characteristic of this subline was its enhanced growth after the addition of a pulmonary extract obtained from nude mice. The relationship of these findings to the mechanisms of metastasis of this cancer was discussed.