INHIBITION BY GINSENOSIDE RG(3) OF BOMBESIN-ENHANCED PERITONEAL METASTASIS OF INTESTINAL ADENOCARCINOMAS INDUCED BY AZOXYMETHANE IN WISTAR RATS

The effects of concomitant use of bombesin and ginsenoside Rg(3) on th e incidence of peritoneal metastasis of intestinal adenocarcinomas ind uced by azoxymethane were investigated in male inbred Wistar rats, Fro m the start of the experiment, rats were given weekly s.c. injections of azoxymethane (7.4 mg/kg body weight) for 10 weeks and s.c. injectio n of bombesin (40 mu g/kg body weight) every other day, and from week 20, s.c. injections of ginsenoside Rg(3) (2.5 or 5.0 mg/kg body weight ) every other day until the end of the experiment in week 45. Bombesin significantly increased the incidence of intestinal tumors and cancer metastasis to the peritoneum in week 45. It also significantly increa sed the labeling index of intestinal cancers, Although administration of a higher dose of ginsenoside Rg(3) with bombesin had little or no e ffect on the enhancement of intestinal carcinogenesis by bombesin, the location, histologic type, depth of involvement, infiltrating growth pattern, labeling and apoptotic indices and tumor vascularity of intes tinal cancers, it significantly decreased the incidence of cancer meta stasis. These findings indicate that ginsenoside Rg(3) inhibits cancer metastasis through activities that do not affect the growth or vascul arity of intestinal cancers.