Tumor angiogenesis factors produced by cancer cells

Tumor angiogenic activity from tumor angiogenesis factors (TAFs) produced by 25 cell lines was assayed onto chorioallantoic membranes (CAMs). Neovascularization occurred prominently in such cell lines, as HTBOA (poorly differentiated ovarian carcinoma), HUOCA-II (poorly differentiated clear cell adenocarcinoma), HWUA (poorly differentiated endometrial adenocarcinoma), HKUS (uterine cervical small cell carcinoma), and in HOTHC (anaplastic thyroid carcinoma). The cell lines which secreted TAF showed high heterotransplantability in nude mice and produced rapidly growing tumors which were rich in blood vessels. The TAFs polypeptides of 14,000 and 78,000 molecular weight, were extracted and purified from the conditioned medium of HUOCA-II or W3UF (sub-line of HUOCA-II) lines, respectively. TAFs at concentrations of 10 ng/ml and 100 ng/ml promoted proliferation of the endothelial cells and induced tube formation. Microsequencing analysis revealed that TAF of 78,000 molecular weight has sequence identity with human hepatocyte growth factor (hHGF).