The Study On Anti-tumour Effects Of Ginsenoside Rh₂ And Rg₃ From Panax Notoginseng On Inhibiting Proliferation And Anti-angiogenesis In Rat With B₁₆ Transplanted Melanoma

Objective:To study the anti-tumor effect of ginsenoside Rh₂ and Rg₃ from Panax notoginseng through in vivo experiment on the basis of rat model with transplanted B₁₆melanoma,further more,to explore the possiable mechanism at the view of anti-angiogenesis.Methods:(1)Found rat modal with transplanted B₁₆melanoma which were randomly divided into 9 groups,include the Rh₂ or Rg₃ with high dose group,the middle dose group and the low dose group,the Rh₂ combined Rg₃ group,the CTX group and the modle group.From the second day of inoculation,all rats were administrated respectively once a day for 10 days,except the CTX group injected intravenously once in another day for 3 times.In the process of experiment, observe the general conditions,weight and death.Until 15^thday,mice were sacrificed to assay inhibitory rate of tumor and cound the thymus and spleen index,blood were obtained from vein of eyeball and centrifuged,the content of IL-2 and TNF-αin serum were detected with radioimmunoassay.(2)Found rat modal with transplanted B₁₆melanoma which were randomly divided into 6 groups,include the modle group,the Rh₂ group,the Rg₃ group,and Rh₂ combined with high dose Rg₃,the middle dose Rg₃ and the low dose Rg₃ groups.All animals were administrated respectively once a day for 10 days,Until 15^thday,they were sacrificed,and separate the tumor tissue fixed with 10%formalin,imbeded with paraffin.Observing the morphological changes of tumor tissue with light microscope after H-E staining.Detecting the vasculogenic mimicry by the mothed of double staining using CD31 and PAS,S-100 and PAS.Detecting the protein expression of VEGF,EphA2,Laminin,MMP-2 and VE-cadherin in neoplastic tissues with immuno-histochemical method.Results:(1)All mice entered the final analysis without loss.In the process of experiment,we found the general condition of rats in the modal group and CTX group get worse gradually.The rats in these two groups become poor appetite,emaciated,and the fur became lacking gloss,even depilate and sluggish,especially CTX group.But in each Rh₂ and Rg₃ groups,the general condition of animals is better than the modal and CTX groups.In additional,when seperating the tumor tissue,we found tumor of rats in the modal group present infiltrative growth,there are abundant tumor vesseles,and it is difficult to strip the amicula.Although in other groups, the tumor tissue have relatively complete amicula,less tumor vessel and is easy to strip, especially each Rh₂ group and Rh₂ combined Rg₃ group.(2)Comparing with pretherapy,the rats in modal and CTX groups lose weight obviously, the organ index reduced,as well as the level of IL-2 and TNF-αin serum,especially CTX group.Administrated Rh₂ and Rg₃ alone or combinedly,both the rats'weight and the immune organs'weight increased in different extent,as well as the level of IL-2 and TNF-α,especially combined groups.There are significant different compared with control groups(P＜0.05).(3)All different dosage of ginsenoside Rh₂ and Rg₃ could remarkably inhibit the growth of B₁₆transplanted melanoma in rats,there are significant difference from average tumor weight of control groups(P＜0.05),espacailly the high and middle dose of Rh₂ group,the high dose of Rg₃ group and the Rh₂ combined Rg₃ group,inhibition rate were 35.5%,30.1%,33.6%and 38.6%respectively.The inhibitation rate of the high and middle dose of Rg3 groups are lower than corresponding dose of Rh₂ groups.(4)Compared the groups administrated Rh₂ and Rg₃ alone or combined with the modal group,both the vascular mimicry density and micro vascular density of tumor tissue are decreased,and the protein expression of CD31 and S-100 are down regulation,obviously each combined groups.(5)It shows that tumor tissue of the modal group expressed the proteins of VEGF,EphA2, MMP-2,VE-cadherin and Laminin,which are all strong positive.Each groups of Rh₂ and Rg₃ can markedly down-regulate the expression of those protein,especially the protein expression of VEGF,EphA2,VE-cadherin,MMP-2,which is more significant in each Rh₂ and Rg₃ combined groups,there are remarkble difference compared with the modal group(P＜0.01 or P＜0.05),and the protein expression of laminin also reduced,but there are not obvious difference between the modal group and each experimental groups.Conclusions:1.The active component Ginsenoside Rh₂ and Rg₃ from Panax notoginseng has a remarkable effect on inhibiting proliferation of B₁₆transplanted melanoma with rat but no obvious side effects.They can improve the animal's whole condition.They don't reduce the weight and inhibit the immune function.It shows that Rh₂ and Rg₃ can improve the life quality of tumor-bearing mice at the same time of anti-tumor. 2.Ginsenoside Rh₂ and Rg₃ from Panax notoginseng can remarkablly inhibit the formation of angiogenesis and vasculogenic mimicry,thus obstruct the blood supply of tumor tissue effectually.3.The possible mechanism of effect of Ginsenoside Rh₂ and Rg₃ from Panax notoginseng on inhibiting vasculogenic mimicry in B₁₆melanoma tissue is related to prevent the activation of EphA2 and down-regulate the expression of MMP-2 and VE-cadherin,thus inhibit the expression and the hydrolization of Laminin.The possible mechanism of their anti-angiogenesis effect is related to down-regulate the expression of VEGF and MMP-2.4.Inhibition of angiogenesis and vasculogenic mimicry probablly is one of the mechanismes of anti-tumor effect of Ginsenoside Rh₂ and Rg₃ from Panax notoginseng.5.It shows combination of Rh₂ and Rg₃ is more efficient on both inhibition of tumor blood supply and anti-tumor.