Abstract: Objective To investigate the effect of taurine combined with NF-κB signaling pathway inhibitor SN50 on the proliferation of hepatocellular carcinoma cells line HepG2 and its mechanism. Methods The expression of p-IκBα and IκBα proteins in hepatoma cells line HepG2 was detected by Western blot after the treatment with 150 mmol/L taurine for 24 hours. HepG2 cells were randomly divided into control group (untreated), taurine group (treated with 150 mmol/L taurine for 24 hours), inhibitor group (treated with 36 μmol/L SN50 for 24 hours) and taurine + inhibitor group (treated with 150 mmol/L taurine and 36 μmol/L SN50 for 24 hours), cell proliferation and apoptosis were examined by MTT, colony forming test and flow cytometry respectively,and cyclin D1, Bcl-2 protein and mRNA were detected by Western blot and RT-qPCR. Results After treatment with 150 mmol/L taurine for 24 hours, the expression of p-IκBα protein in HepG2 cells decreased in a time-dependent manner (P＜0.05). After treatment with 150 mmol/L taurine or 36 μmol/l SN50 for 24 hours, the survival rate and cloning rate of HepG2 cells significantly decreased, the apoptosis rate significantly increased, and the expressions of cyclin D1 and Bcl-2 protein and mRNA were significantly inhibited as compared with the control group, all the differences were statistically significant(P＜0.05).At the same time, SN50 enhanced the inhibitory effect of taurine on the proliferation of HepG2 cells, the expression of cyclin D1 and Bcl-2, and the promotion of apoptosis. Conclusions Combined efforts of taurine with NF-κB signaling pathway inhibitor SN50 inhibit strongly the proliferation of hepatoma cells line HepG2 through NF-κB signaling pathway.

Key words: hepatocellular carcinoma, taurine, NF-κB signaling pathway, cell proliferation, apoptosis