Growth-inhibitory effect of hexa-N-acetylchitohexaose and chitohexaose against Meth-A solid tumor.

Abstract

Two oligosaccharides, hexa-N-acetylchitohexaose (NACOS-6) and chitohexaose (COS-6), consisting solely of N-acetyl-D-glucosamine and D-glucosamine, respectively, were found to be growth-inhibitory against Meth-A solid tumor transplanted into BALB/c mice, when each oligosaccharide was administered i.v. at a dose of more than 1 mg/kg. Mouse peritoneal macrophages elicited with casein underwent activation with these oligosaccharides in vitro to produce interleukin 1. Spleen cells from mice given these oligosaccharides also underwent acceleration of interleukin 2 production and cytolytic T-lymphocyte differentiation. Thus, the antitumor mechanism of NACOS-6 and COS-6 was assumed to involve increased production of lymphokines including interleukins 1 and 2, sequentially, leading to the manifesation of antitumor effect through proliferation of cytolytic T-lymphocytes.