Establishment and properties of a human choriocarcinoma cell line of ovarian origin.

A human nongestational choriocarcinoma cell line of ovarian origin (IMa) was established in vitro. This cell line had been subcultured serially more than 22 times over 18 months. Small polygonal cells with a prominent nucleus were dominant and a sparsity of cytoplasmic organelles was an ultrastructural characteristic of the IMa cells. The production and secretion of human chorionic gonadotropin and its subunits were identified by radioimmunoassay. The IMa cells were transplantable in the hamster cheek pouch and the histological diagnosis was choriocarcinoma. A newly established ovarian choriocarcinoma cell line can be considered useful for clarifying the biological differences between nongestational and gestational choriocarcinoma cells.