Effects Of SBE On Immune Function Of Immunosuppressive Mice And Human Orthotopic Hepatocellular Carcinoma Transplanted In Nude Mice

The influence of soybean extract (SBE) on immune function of immunosuppressive micewas investigated in present study. The inhibitory effects of SBE on human orthotopictransplanted hepatocellular carcinoma (HCC) of nude mice and the mechanisms ofregulating the cell cycle were also investigated. In part I, immunosuppressive mice wasestablished by intraperitoneal injection of cyclophosphamide (CTX) to investigate theeffect of SBE on immune function of immunosuppressive mice. The data indicated thatspleen index and IgG2a level were significantly increased. The peripheral leucocytecount and the percentage of mononuclear leucocytes and neutrophils were markedlyraised. The activity of NK cell and peritoneal macrophage was remarkably stimulated.SBE significantly increased the immune function of CTX-induced immunosuppressivemice. Since SBE was shown to increase the immune function of CTX-inducedimmunosuppressive mice, we examined whether SBE would inhibt the growth of HCC.In part II, to combine our previous findings of HCC, the experimental model of humanorthotopic transplanted HCC of nude mice in vivo was used to investigated inhibitoryeffects of SBE on bearing cancer nude mice. We focused mainly on the cell cyclechanges of hepatocellular carcinoma cell. It was found that the growth of humanorthotopic transplanted HCC was inhibited by SBE. The peripheral leucocyte count ofnude mice was increased and AFP level of blood serum was decreased. Hepatic functionof bearing cancer nude mice was ameliorated by SBE. The hepatocellular carcinoma cellcount of G1 phase was significantly increased in SBE 30mg/kg group. The principalmechanism may relate with the changes in the expression of p21, Cyclin D1/CDK4,Cyclin E/CDK2 and P-pRb. The upregulation of p21 and downregulation of CyclinD1/CDK4, Cyclin E/CDK2 and P-pRb were related with G1 cell arrest and influencedthe G1/S transition.