Fibrinolysis induced by rat glioma cells. A mitosis-triggered process?

Experimentally induced brain glioma cell lines were studied in cell cultures for their fibrinolytic activity; simultaneously the mitotic index was determined. It was found that the most intense fibrinolytic activity of glioma cells coincides with mitotic waves. After 68 hr incubation of SD/G1 cells on a [125I]fibrin layer, [125I]fibrin digestion products were examined by gel chromatography. Hydroxy-urea and actinomycin D were used as inhibitors in cell cultures, investigating their effect on the expression of fibrinolysis. These studies reveal that [125I]fibrin digestion products are mainly low molecular weight (less than 12,000 daltons) compounds and that fibrinolysis is partially inhibited by the drugs added.