Aglaroxin C Inhibits Hepatocellular Carcinoma Growth In Vitro And In Vivo

BackgroundHepatocellular carcinoma（HCC）is one of the most common frequent deadly malignancies in worldwide^[1-3].Investigations have revealed that the incidence of liver cancer is the third of malignant tumors in China,and the mortality in China’s cities is second to lung cancer.Nowadays,although the surgery of liver cancer,transcatheter arterial chemoembolization and biological target therapy have improved,the therapeutic effect of hepatocellular carcinoma is still unsatisfactory,the estimated 5 year overall survival rate is about 10%.Rocaglamide was isolated from Aglaia elliptifolia of Melia in1982 and was shown to increase the median survival time of tumor-bearing mice in the P388 Lymphocytic Leukemia model.Recently,Santagata showed that Rohinitib（RHT）had a strong antitumor effect by inhibiting HSF1 activity and glucose uptake.Stone SD indicated that Rocaglamide derivatives Aglaroxin C has similar effect compared with RHT.Studies on the Aglaroxin C have not been reported in the literature.ObjectiveTo assess the effect of Aglaroxin C on human hepatocellular carcinoma growth in vitro and to evaluate its antitumor activity in tumor-bearing mice.Methods1.The human hepatocellular carcinoma cell line HepG2 were cultured in vitro.Increasing concentrations of Aglaroxin C and Cisplatin were added to the logarithmic growth phase cells,respectively.The cell inhibition ratio were determined by cell counting kit-8（CCK-8）assay 24,48,72 hours thereafter,calculating the half inhibitory concentration of Aglaroxin C and the proliferation toxicity of hepatoma cells.2.Establishment of hepatoma transplant tumor model.Tumor-bearing animals were randomly divided into five groups:tail vein control group,0.1mg tail vein group,intratumoral administration control group,0.05mg and 0.1mg intratumoral administration group.Give medicine every other day,four times.Changes in tumor volume were measured before and after treatments and growth curves were plotted.24 hours after the last drug administration,tumor tissues were also dissected out and the tumor inhibition rate was calculated.Part of the tumor tissue was HE stained for observing pathological changes under the microscope.Results1.In vitro experiments show that Aglaroxin C inhibited the growth of HepG2 cells in a dose-dependent manner(F_24h=175.64,F_48h=37.36,F_72h=36.35,P<0.05).The IC₅₀ of HepG2 cells treated with Aglaroxin C for 24 h,48 h,72 h were 73 nM,25 nM,82 nM,respectively.The proliferation inhibition rate between 10nM Aglaroxin C group and 5μM Cisplatin group,the difference is not statistically significant（P>0.05）.Under the microscope,with the increase concentration of Aglaroxin C,the number of hepatoma cells gradually decreased,cell morphology became round,shrinkage,loss of polarity,decreased ability to adhere to the wall and the number of dead cells increased.2.In vivo experiments show that the tumor volume and mass of treatment group were significantly smaller than that of the control group under the same administration（P<0.05）.The tumor volume and mass of the 0.1mg intratumoral administration group was significantly less than that of the 0.1mg tail vein group under the different administration（P<0.05）.There was no significant difference between that of the 0.05mg intratumoral administration group and the 0.1mg tail vein group（P>0.05）.The tumor inhibition rates of0.1mg tail vein group,0.05mg and 0.1mg intratumoral administration group were 24.64%,27.83%,53.91%,respectively.ConclusionAglaroxin C treatment significantly inhibits the proliferation of HepG2 hepatoma cells in vitro and in vivo tumor growth using the H22 hepatoma bearing mice.Aglaroxin C may potentially be the new drug for the treatment of liver cancer in future.