[A new strategy for malignancies by direct hemoperfusion using bacterial endotoxin bounded fiber].

Endotoxin derived from E.coli was chemically bounded to polystryen fiber (LPS immobilized fiber). Anti-cancer activities of LPS immobilized fiber (LPS-F) were evaluated by a single direct hemoperfusion (DHP) on the VX2 tumor-bearing rabbits. Examination I: Cancer-bearing rabbits were prepared by intradermal injection of 4 X 10(5) of VX2 tumor cells into the back. Five out of 11 (Group 1) were treated with DHP at 4-5th day, and 6 out of 10 (Group 2) at 7-9th day. Examination II: Seventeen out of 19 tumor-bearing rabbits were injected of 9.38 X 10(7) viable BCG intravenously. Next day they were implanted 1 X 10(6) of VX2 tumor into the thigh muscle. Twelve out of 17 were treated with DHP at 14 days after BCG infection (treated group). Other five of 17 belonged to the control group and two were not treated. Tumor growth were significantly suppressed in both groups (p less than 0.05). Survival rate was 2/5 (40%) in and 1/5 (20%) in group 2 and 0% in non-treated group. In examination II, survival rate were 8/12 (treated), 2/5 (BCG infected) and 0/2 (non-treated) respectively. In histological study, bleeding and tumor cell necrosis were found in tumor at 6 hr after DHP. DHP using LPS-F had tumoricidal activities on the VX2 tumor of rabbits. In BCG infected rabbits, this treatment could cause tumor necrosis and produce multiple humoral factors with tumoricidal activities.