Establishment of HUOCA-II, a human ovarian clear cell adenocarcinoma cell line, and its angiogenic activity

A cell line designated "HUOCA-II" was established from a human ovarian clear cell adenocarcinoma. The HUOCA-II cells, which were oval, spindle, or polygonal and had neoplastic and pleomorphic features, grew in multiple layers without contact inhibition. The cell line grew fast (population doubling time, 24 hr), and 55 serial passages were carried out within 11 months. The chromosomal number ranged around 46, and no karyological abnormality was found in G-band karyotyping. When heterotransplanted into the subcutis of BALB/c nude mice, HUOCA-II cells produced a poorly differentiated clear cell adenocarcinoma. The tumor angiogenesis factor (TAF) of a molecular weight of about 14,000 was purified from the conditioned medium of HUOCA-II cells, and neovascularization was detected by bioassay with the use of the chorioallantoic membrane of a chick embryo. This TAF also stimulated the growth of endothelial cells in an in vitro culture system.