The present study is designed to explore an anti-tumor activity on crude extracts of Oplopanax elatus. Water extractions of Oplopanax elatus were performed at 100℃(OeE-100). OeE-100 doses up to 62.5 ㎍/㎖ had no cytotoxicity on the tumor cell lines in vitro. In experimental lung metastasis of colon26-M3.1 carcinoma or B16-BL6 melanoma, the prophylactic intravenous (4~100 ㎍/mouse) or oral (2 ㎎/mouse) administration of OeE-100 significantly inhibited tumor metastasis as compared with tumor controls. Peritoneal macrophages stimulated with OeE-100 produced various cytokines such as TNF-α, IL-6 and IL-12. In an analysis of NK-cell activities, i.v. administration of OeE-100 (10~100 ㎍/mouse) significantly augmented the cytotoxicity to YAC-1 tumor cells. Vaccination of mice with boiling-treated tumor cells (BT-vaccine) in combination with OeE-100 (100 ㎍/mouse) showed higher inhibitions in tumor metastasis when compared with the mice of BT-vaccine treatment. In addition, the splenocytes from OeE-100 admixed BT-vaccine immunized mice secreted a higher concentration of Th1 type cytokine such as IFN-γ. These results suggested that the OeE-100 stimulated immune system and was a good candidate adjuvant of anti-tumor immune responses.

In this study we investigated the effects of supplementation with fucoidan from brown alga on the function of natural-killer (NK) cells to evaluate the possibility as an immunomodulator in ovariectomized (OVX) rats. A total of 18 female Wistar rats (six weeks) were used this study and 12 rats were OVX, and the rest of rats were sham-operated. The sham and one OVX group were fed standard diet, and the remaining OVX group received fucoidan (0.05% supplemented diet). After 12 weeks of supplementation, rats were sacrificed to assess the tumoricidal activity of the NK cells and the NO-iNOS regulation from splenocytes. The mass of body and the immune organs such as spleen and thymus were also studied. In OVX rats, body and thymus weights increased, however fucoidan supplementation did not change the body mass and organs weight compared to OVX group. Fucoidan supplementation increased NK cell activity and reduced NO-iNOS production in OVX rats. Ex vivo treatment of fucoidan increased NK cell activity in splenocytes from shame and OVX rats. Ex vivo, we confirmed that fucoidan partially reduced the NK cell activity in the presence of iNOS inhibitors in OVX-splenocytes. These results indicate fucoidan supplementation has a NK cell tumoricidal activity, which are regulated by the iNOS production in OVX rats. This suggests that fucoidan is useful for potential therapeutic strategies as a nutrient in regulating the NK cells in postmenopausal osteoporosis patients.