Antitumor and Immunostimulating Activities of Elfvingia applanata Hot Water Extract on Sarcoma 180 Tumor-bearing ICR Mice

Elfvingia applanata, a medicinal mushroom belonging to Basidiomycota, has been used in the effort to cure cancers of the esophagus and stomach, and is also known to have inhibitory effects on hepatitis B virus infection. The hot water soluble fraction (as Fr. HW) was extracted from fruiting bodies of the mushroom. In vitro cytotoxicity tests showed that hot water extract was not cytotoxic against cancer cell lines such as Sarcoma 180, HT-29, HepG2, and TR at concentrations of 10~2,000 µg/mL. Intraperitoneal injection with Fr. HW resulted in a life prolongation effect of 45.2% in mice previously inoculated with Sarcoma 180. Treatment of Fr. HW resulted in a 2.53-fold increase in the numbers of murine spleen cells at a concentration of 50 µg/mL, compared with control. Incubation of murine spleen cells with Fr. HW at a concentration of 500 µg/mL resulted in improved immune-potwntiating activity of B lymphocytes through an 8.3-folds increase in alkaline phosphatase activity, compared with control. Fr. HW generated 12.5 µM of nitric oxide (NO) when cultured with RAW 264.7, a mouse macrophage cell line, at the concentration of 50 µg/mL, while lipopolysaccharide, a positive control, produced 15.2 µM of NO. Therefore, the results suggested that antitumor activities of Fr. HW from E. applanata might, in part, be due to host mediated immunostimulating activity.