Abstract
Transplantability of three different tumor cell lines derived from human malignant astrocytoma (Gl-MK) and glioblastomas (Gl-AK and Gl-WI) in nude mice was established. All these tumors histologically resembled the original ones, and immunoperoxidase preparations demonstrated the presence of S-100 protein and glial fibrillary acidic protein (GFAP).
Using two of these tumors (Gl-MK and Gl-AK), experimental studies were carried out to determine the antitumor effect of the human fibroblast interferon (IFN-β). 6×102 to 6×104 IU/ml IFN-β supressed the growth of cultured Gl-MK cells. In a flow-cytometric study, tumor cell growth in the S phase 48 hours after administration of IFN-β and after 72 hours, inhibition of tumor cell growth in the early S phase were observed. When administerd repeatedly, 100 IU/ml of IFN-β showed an adequate anti-tumor effect.
Intraperitoneal administration of IFN-β 50×104IU every other day for four weeks resulted in transient regression of Gl-MK tumor transplanted into nude mice. Intra-tumoral injection of IFN-β 60×104 IU every day for six or ten weeks produced a significant inhibitory effect on tumor growth of both tumor cell lines transplanted into nude mice, and significant degenerative changes in the tumor tissue were revealed by histological and electron microscopical examinations.
Eight clinical cases consisting of four glioblastomas, three malignant astrocytomas, and one medulloblastoma—seven of which were recurrent—were treated intrathecally and/or intravenously with IFN-β in doses of 30×104 to 600×104IU every day. The results were evaluated according to Karnofsky's scale, and the tumor size on CT scans were as follows: one showed partial remission (glioblastoma), four were stable, and three showed progression. High fever, leukocytopenia, and thrombocytopenia occurred in one case and were considered to be side effects of the medication.
