Recombinant Allophycocyanin Immune Regulation And Anti-angiogenic Biological Activity

Objective:This study was to investigate the anticancer function by giving different doses of rAPC in H22 cell, and discussed the mechanism from the immune and antiangiogenic aspects.Methods:1.Animal grouping and model:Fifty Kunming mice were fed for adaptability for one week after buying, Each mice was vaccinated 0.2 mL concentration for 2×106/ mL of H22 tumor cells suspension liquid in right fore axillary subcutaneously.24 hours later, they were randomly divided into five groups:model group (A):normal saline(0.5ml/d) was given by gastric perfusion; rAPC groups (B,C,D):respectively rAPC low-dose,mid-dose,high-dose intervention groups, rAPC (25,50,100mg/kg-d) was given by gastric perfusion respectively; CY group (E):CY (40mg/kg-d) was given by peritoneal injection. And each group had ten mice. ABCD groups were given continuous dosage for two weeks while E group was given CY every other day.2. Inhibition rate and immune function evaluation:(1) 24h after last medication, the mice were weighed and put to death. The mice were dissected under sterility condition. Dissected tumors and weighed them exactly, and calculated the tumor inhibition ratios. Tumor inhibition ratio=(average tumor weight of control group-average tumor weight of group)/average tumor weight of control group×100%. (2) organ index:weighed thymus and spleen and calculated spleen index and thymus index.spleen index:spleen index= spleen weight(mg)/body weight(g). (3) related cytokines determination:RIA method was used to determinate the levels of IL-6 and TNF-α.3. Antiangiogenic function evaluation:Immunohistochemistry methods were used to detect the VEGF,PCNA,COX-2 expressions in tumor tissue.Results:1.Inhibition rate:Compared with the model group, the tumor growth in H22 of low-dose rAPC group was slower(P<0.05), the tumor growth of mid-dose and high-dose group was siginificantly slower(P<0.01), and the inhibition rates were respectively: 25.2%,36.7%,43.1%.2. Immunity activity:Indexes of thymus of all doses of rAPC increased, which had significant difference(P<0.01) with model group, the indexes of spleen of mid-dose and high-dose groups were higher than model group, and have statistical significance(P<0.05); the spleen index of low-dose group had no significant difference(P>0.05); The IL-6 and TNF-a level in serum in rAPC low-dose and mid-dose groups were higher than that in model group, and of statistics significance(P<0.05), the IL-6 and TNF-αlevel in serum in rAPC high-dose group was higher than that in model group, and had significant difference(P<0.01).3. Antiangiogenic:COX-2 masculine expression of all doses of rAPC were slower than the model grou(P＜0.01); VEGF masculine expression of all doses of rAPC were slower than the model group(P<0.01); PCNA masculine expression of mid-dose and high-dose groups siginificantly reduced than the model group.Conclusion:rAPC can promote the growth of mice thymus and spleen, and improve the immune function of animals and can inhibit tumor angiogenesis.