Abstract
The 50% ethanolic extract (ONG-ext) of “Ongael” [leaves of Phaleria cumingii (MEISN.) F. VILL.] inhibited proliferation of mice mammary carcinoma cells (MM46) and human leukemia cells (HL60) at a concentration of 50 to 200 μg/ml. Mangiferin (1), a major constituent of ONG-ext, showed antiproliferative activities on MM46 and HL60 cells at a concentration of 100 μg/ml. Oral administration of ONG-ext (50 and 500 mg/kg) and 1 (10, 50 and 100 mg/kg) to MM46 cells transplanted C3H/HeN mice showed significant antitumor effects. In HL60 cells transplanted C.B-17/Icr SCID mice, ONG-ext (50 and 500 mg/kg, p.o.) showed no significant antitumor effect. On cytokines production in the spleen isolated from MM46 carcinoma bearing mice, ONG-ext (500 mg/kg, p.o.) and 1 (100 mg/kg, p.o.) significantly inhibited the reduction of tumor necrosis factor (TNF)-α and interleukin (IL)-2 levels, and ONG-ext (500 mg/kg, p.o.) increased interferon (IFN)-γ level compared to that of vehicle control group. As to in vitro mitogen response of mice spleen T cells in the presence of sample-treated macrophage, ONG-ext (25, 50 μg/ml) and acylglucosylsterol (2) (10 μg/ml) significantly increased both TNF-α and IFN-γ levels. It has been indicated that the in vivo antitumor effect of ONG-ext partly depends on immunostimulatory activity, and active constituents are 1 and 2.
