Autolysis induction of malignant lymphoblasts.

BALB/C mice were treated with epsilon aminocaproic acid (EACA), 0.1 to 3.2 mg/g body weight, subcutaneously every 24 hours for six days, starting on the second day after intraperitoneal transplantation of L5178Y lymphoma. Complete involution was observed in 20 to 90 per cent of the ascitic tumor and in 50 per cent of the solid tumor 72 hours after EACA was discontinued, tumoral involution and dosage were directly proportional. One hundred per cent of the non treated controls died 10 +/- 0.6 days after intraperitoneal lymphoma transplantation. During tumor involution malignant cells underwent autolysis and were attacked or phagocytized by activated macrophages. Since EACA is a proteolytic enzyme inhibitor, inhibition during treatment and activation of these enzymes after EACA was discontinued could have been the cause of autolysis of the L5178Y lymphoma cells.