Study Of The Antitumor Activity And The Mechanisms Of Phycoerythrin From Gracilaria Lemaneiformis

In our study,the antitumor effect of Phycoerythrin(PE) from Gracilaria Lemaneiformis, collected from the sea area around Nan'ao Island,Shantou city,Guangdong province was studied.Throuth the methods of immune response of mice beating H₂₂ hepatocellular carcinoma and effection to transcription of p53 and Caspese-3 gene to discuss the effection and mechanism of the anti-tumor activity of PE.The antitumor experiments indicated that the Phycoerythrin could significantly inhibit the growth of H₂₂ hepatocellular carcinoma.At the dose of 300mg·kg^-1 when given irrigatively(ig),the inhibition rate was 30.23%.The tests of superoxide dismutase(SOD) activity in red blood cell and lipoperoxide(LPO) level in liver homogenate suggested that the anticancer effect of phycobiliprotein might be related to its antioxidation.The results showed that PE can stop the decrease of body weight caused by tumor-beating and protect spleen and thymus gland and improved their activities.The results also showed that crude Phycoerythrin from Gracilaria lemaneiformis can improve lymphocyte responses induced by ConA of tumor beating mice,increased spleen cell turn to lymphocyte.PE can increase the activity of macrophage and natural killer cell,the adhesive ability of erythrocyte immunity to tumor cells and the production of TNF-α.the result showed that maybe increase the immune response of mice beating H₂₂ hepatocellular carcinoma to inhibit the growth of the tumor,even cause the tumor to apoptosis.The effect of PE to the transcription of p53 and Caspese-3 gene in the tumor of mice beating H₂₂ hepatocellular carcinoma was studied by semi-quantitaty RT-PCR. The result showed that in vivo mRNA of p53 and Caspese-3 gene in the tumor of mice beating H₂₂ hepatocellular carcinoma given irrigatively(ig) PE is over-expressed.But inhibitory effect and over-expression is not found,in vitro.The immunodeficiency mice mode(IDMM) was estabulished with Cyclophosphamide injected.The immunoregulatory activity of polysaccharides from Gracilaria lemaneiformis(PGL) was studied.The results showed that PGL could enhance immune- funcation of immnodepressive mice.But the results showed that there's no does-effect relationgship between activity of PGL enhancing immunofuncation and PGL.does-effect relationgship between activity of enhancing immunofuncation and contents of sulphate in PGL was not found.