Effects Of Curcumin, Demethoxycurcumin And Bisdemethoxycurcumin On Expression Of Survivin, Livin Proteins In Human Hepatoma Cell Line HepG2

Objective: Hepatocellular Carcinoma (HCC) is a common digestivecancer in our country and the world, China has the highest incidence of livercancer in the world, accounts for more than half of the new incidence.Mortality of HCC ranked second in all tumor in China’s mainland area, andthe mortality is on the rise in recent years. Because the early symptoms ofHCC are not typical, and progress rapidly, most patients have been so late thatlose the chance of radical resection when they found. The malignant degree ofHCC is high, the average survival time of middle-late patients who withouttreatment was only three months,5years of survival rate is only15%-40%,and60%-80%of patients relapse within two years.Survivin protein and mRNA express higher in human tumor cells,Survivin can anti-apoptosis, adjust the cell mitosis, promote cell proliferation,participate the formation of vessels, and so on. Survivin is highly expressed inliver cancer tissue and all the human hepatoma cell line, but was not found incirrhosis and the adjacent tissues. High expression of Survivin is closelyrelated to the formation of portal vein tumor emboli and tumor relapse aftersurgery. Some studies found that, inhibit the expression of Survivin proteinand its mRNA, could significantly inhibit the growth and proliferation oftumor cells, improve the effect of treatment. Livin protein expressed low or noexpression in most adult normal tissue, but increased in most malignant tumortissues. Its’ high expression are closely related to tumor differentiation degree,invasion and metastasis, etc. The expression positive rate of Livin protein inHCC is significantly higher than the adjacent tissues and normal liver tissue.High expression of Livin and Survivin is closely related to the occurrence,development, metastasis, prognosis, etc of HCC. Curcumin demethoxycurcumin and bisdemethoxycurcumin is extractedfrom the rhizome of turmeric zingiberaceae plants, and as a traditionalChinese medicine composition used in our country also has a long history.Curcumin, demethoxycurcumin and bisdemethoxycurcumin has anti-oxidant,anti-inflammatory, anti-infection, anti-atherosclerosis, anti-fibrosis, anti-tumor,and so on. Because of curcuminoids have good antitumor effect, westernmedicine have paid more attention and research on curcuminoids in recentyears.In recent years, some scholars found that curcumin, demethoxycurcuminand bisdemethoxycurcumin can inhibit breast cancer, gastric cancer, intestinalcancer and liver cancer cells proliferation and promote apoptosis of tumorcells, this may be associated with down-regulate the expression of Survivinprotein and its mRNA, but the specific mechanism remains to be furtherresearch. About the adjustment of curcuminoids on Survivin and Livin in HCCare rare reported. This experiment through research the expression of LivinSurvivin protein in HepG2cells after treatment with curcumin,demethoxycurcumin and bisdemethoxycurcumin, to preliminary discussionthe mechanism of curcuminoids to promote HepG2cells apoptosis.Methods: Cultivate Hepatocellular carcinoma cell line HepG2in general.After HepG2cells were treated with the same concentration (20umol/L) ofcurcumin, demethoxycurcumin, bisdemethoxycurcumin for24h, and theapoptosis rate was measured by flow cytometry(FCM). HepG2cells weretreated with different concentrations(20μmol/L,40μmol/L) of curcumin,demethoxycurcumin, bisdemethoxycurcumin for24h, protein levels of Livin,Survivin were detected by Western blotting. Preliminary reasearch theadjustment of Livin, Survivin protein under curcumin, demethoxycurcuminand bisdemethoxycurcumin in HepG2cells.Results:1. Analysis by FCM showed that the apoptosis rate of HepG2cells were significantly higher after treatment with curcumin,demethoxycurcumin and bisdemethoxycurcumin than the blank control group(P<0.05), the effect of bisdemethoxycurcumin is better than curcumin and demethoxycurcumin (P<0.05), there was no significant difference between thegroup with curcumin and demethoxycurcumin (P>0.05).2. After HepG2cells treatment with Curcumin, demethoxycurcumin,bisdemethoxycurcumin at different concentrations (20,40umol/L) were testedby Western-Blot analysis, the expression of Survivin, Livin protein in HepG2cells was lower than the blank control group (P<0.05), and the expressionlevels of Livin, Survivin protein are decreased with the increase ofconcentration (P <0.05).3. Livin and Survivin protein inhibition strength followed bybisdemethoxycurcumin> demethoxycurcumin> curcumin (P <0.05).Conclusion: Curcumin, demethoxycurcumin and bisdemethoxycurcumincan obviously induce the apoptosis of HepG2cells. Curcumin,demethoxycurcumin, bisdemethoxycurcumin can down-regulated theexpression of Survivin, Livin in HepG2cells, and their strength in the orderbisdemethoxycurcumin> demethoxycurcumin>curcumin.