Effects of Ferulic Acid on the Proliferation ，Invasion and Apoptosis of HepG 2 Hepatocellular Carcinoma Cells / 中国药房

ABSTRACT

OBJECTIVE：To study the effects of ferulic acid on t he proliferation ，invasion and apoptosis of HepG 2 hepatocelluar carcinoma cells. METHODS ：CCK-8 assay was used to screen the concentration of ferulic acid. Western blot assay was adopted to screen the optimal concentration of interleukin 6（IL-6）to induce HepG 2 cell model with high expression of phosphorylated signal transduction protein and activator 3（p-STAT3）protein. HepG 2 cell were divided into blank control group ， model group ，ferulic acid group （0.5 mmol/L）and positive control group （p-STAT3 inhibitor C 188-9，10 μmol/L）. Except for blank control group ，model group treated with IL- 6，while administration groups were treated with IL- 6 and relevant drugs. Cell survival rate ，invasion and apoptosis rate in early and late stage were detected by CCK- 8 assay，Transwell assay and Annexin V-FITC/PI double staining ，respectively. Western blot assay was used to detect the expression of p-STAT 3，caspase-3，ZBP-89 and vimentin proteins in each group. On the basis of the PDB protein database ，using 1BG1，a highly similar crystal structure of STAT3，as docking template ，using the region around Tyr 705 as the putative binding pocket ，the docking analysis of ferulic acid with STAT 3 protein was carried out. RESULTS ：It is selected to use 0.5 mmol/L ferulic acid intervention for 48 h as the follow-up experimental condition ；50 ng/mL IL- 6 was selected as the modeling condition. Compared with blank control group ，the number of cell invasion ，p-STAT3/STAT3 ratio and protein expression of vimentin were increased significantly in model group （P＜0.05 or P＜0.01），while late apoptosis rate and protein expression 20 of caspase- 3 were decreased significantly （P＜0.05 or P＜ 0.01）. Compared with model group ，cell survival rate ，the number of cell invasion ，p-STAT3/STAT3 ratio and protein expression of vimentin were d ecreased significantly in ferulic acid group and positive control group （P＜0.05 or P＜0.01）；early apoptotic rate （except for ferulic acid group ），late apoptotic rate，the protein expression of caspase- 3 and ZBP- 89（except for positive control group ）were increased significantly （P＜0.05 or P＜0.01）. The results of molecular docking showed that the carboxylic groups of ferulic acid could interact with 1.9 Å hydrogen bond of Asn 581 and 2.0 Å hydrogen bond of Lys 591，with binding energy of －4.4 kcal/mol. CONCLUSIONS ：Ferulic acid may inhibit the activity of p-STAT 3 by directly binding to the phosphorylation site of STAT 3；it may up-regulate the protein expression of caspase- 3 via STAT 3 dependent pathway ，or up-regulate the protein expression of ZBP- 89 via STAT 3 independent pathway and then down-regulate the protein expression of vimentin ，so as to inhibit the proliferation ，invasion and apoptosis of HepG 2 cells.