Thromboplastic and fibrinolytic activities of ascites tumor cells of rats, with reference to their role in metastasis formation.

Thromboplastic and fibrinolytic activities of rat ascites tumor cells avoiding any stromal elements were examined and the role of these activities in the blood-borne metastasis was discussed. Ten lines of tumor cells showed varied thromboplastic and fibrinolytic activities. Tumor cell lines examined were classified into four groups; (1) lines AH-130, AH-62, and AH-7974 with high thromboplastic and high fibrinolytic activities, (2) lines AH-130F(N), AH-66F, and AH-7974F with low thromboplastic and low fibrinolytic activities, (3) line SLC with high thromboplastic and low fibrinolytic activities, and (4) lines AH-109A, AH-41A, and AH-41C with moderate thromboplastic and low fibrinolytic activities. The cell lines AH-130 and AH-130F(N), as well as AH-7974 and AH-7974F, have the same origin and showed different enzymic activities. AH-130 caused more prominent thrombus formation in the pulmonary vessels of rats in the early stage of intravenous inoculation and induced more prominent decrease in the number of platelets and fibrinogen levels in peripheral blood than AH-130F(N). Also, AH-130 developed more abundant metastatic foci in the lung 72 hr and 7 days after intravenous inoculation than AH-130F(N).