Abstract: Objective To investigate the therapeutic effects of total saponins from Panax notognseng (PNS) combined with cyclophosphamide (CTX) in mice bearing hepatocellular carcinoma H22 cell xenograft. Methods We examined the effects of treatment with different concentrations of PNS on H22 cell proliferation for 24 to 72 h in vitro using CCK8 colorimetric assay. Annexin V/PI double fluorescence staining was used to detect the effect of PNS on apoptosis of H22 cells. Mouse models bearing H22 cell xenograft were established and treated with CTX (25 mg/kg), PNS (120, 240 or 480 mg/kg), alone or in combinations. After treatments for consecutive 10 days, the mice were euthanized for examinations of carbon clearance ability of the monocytes and macrophages, splenic lymphocyte proliferation, tumor necrosis factor (TNF-α), interleukin-2 (IL-2), serum hemolysin antibody level, blood indicators, and the tumor inhibition rate. Results Treatment with PNS concentration-dependently inhibited the proliferation and significantly promoted apoptosis of cultured H22 cells (P<0.01). In the tumor-bearing mouse models, PNS alone and its combination with CTX both resulted in obvious enhancement of phagocytosis of the monocyte-macrophages, stimulated the proliferation of splenic lymphocytes, promoted the release of TNF-α and IL-2 and the production of serum hemolysin antibody, and increased the number of white blood cells, red blood cells and lymphocytes in the peripheral blood. Treatment with 480 mg/kg PNS combined with CTX resulted in a tumor inhibition rate of 83.28% (P<0.01) and a life prolonging rate of 131.25% in the mouse models (P<0.05). Conclusion PNS alone or in combination with CTX can improve the immunity and tumor inhibition rate and prolong the survival time of H22 tumor-bearing mice.

Key words: Panax notoginseng total saponins; liver cancer; H22 cells; immunity; anti-tumor rate; survival time