EFFECTS OF HOST IMMUNITY ON HEPATIC METASTASIS - RELATIONSHIP BETWEENEFFECTS OF MITOMYCIN-C (MMC) AND OK-432 ON IMMUNITY AND HEPATIC METASTASIS IN AN EXPERIMENTAL-MODEL

The effects of MMC and/or OK-432 on host immunity were studied using a hepatic metastatic model. AH60C cells, which have sensitivity to MMC on the SDI test in vitro, were inoculated before or after administrati on of MMC to the portal vein. The number of hepatic metastases increas ed in both groups. Administration of OK-432 decreased the number of he patic metastases and that of MMC+OK-432 decreased more markedly. The a dministration of MMC decreased the NK activity in the liver, but OK-43 2 improved the hepatic NK activity to the level of the AH60C group and the administration of MMC+OK-432 increased the hepatic NK activity mo re than the OK-432 group alone. The administration of MMC+OK-432 induc ed stronger NK activity than that of the OK-432 alone even at the dose of MMC, that decreased the NK activity. This suggested an interaction between MMC and OK-432. Since anticancer agents that show sensitivity to tumors can sometimes induce hepatic metastasis with the dose of an ticancer unbalancing the host immunity, a good method is then required to monitor the host immunity in chemotherapy. The proper combination between anticancer agents and biological response modifiers which indu ce host immunity is not to be neglected in chemotherapy.