Effects Of 5,7-dimethoxychrysin On The Growth And Apoptosis Of Human Lever Carcinoma HepG2 Cell Line

Objective: The aim of this paper is to investigate induction of the growth inhibition and apoptosis in human lever carcinoma cell line(HepG2) by the deviration of chrysin, 5,7-dimethoxychrysin (dMChR)and provide a molecular mechanism of action so as to find a new candidate for tumor chemotherapy.Methods: Human lever carcinoma cell line (HepG2) cells and human embryo lever diploid cell line (L-02) cells were cultured in vitro. MTT assay was used to determine the effect of dMChR on the proliferation viability of HepG2 cells and L-02 cells and to evaluate the selectivity of action against tumor cells. The cell count of trypan blue staining was used to count the number of viable and dead cells, then the cell survival rate and growth curve were achieved. Apoptosis of HepG2 cell was determined by Flow cytometry(FCM) using PI staining. AO/EB staining was used to observe the morphologic changes of apoptosis induced by dMChR in HepG2 cells. The protein expression and activity of PPARγ, PTEN, p-AKt and Caspase-3 were examined by Western blot to explore the molecular mechanism of anti-lever cancer action of dMChR.Results: dMChR inhibited viability and growth of HepG2 cells in a dose-dependent manner, its efficacy was stronger than that of Chrysin. While there was no significant effect in L-02 cells. The selective index was 21.03. When the cell survival rate was determined by the cell count of trypan blue staining, the results showed dMChR of various concentration 1.0, 4.0, 16.0μM had inhibitory growth effect on hepG2 cell in a dose-dependent manner. dMChR at 16.0μM could prolong hepG2 cell multiple time from 20.51h to 29.72h.Flow cytometry after PI staining indicated that apoptosis in HepG2 cells was significantly induced by dMChR. Typical morphologic changes of apoptosis was observed after treatment with dMChR by fluorescence microscope using AO/EB staining.Western blotting indicated that after exposure to dMChR at 1.0μM, 4.0μM, 16.0μM for 24h, the expression of PPARγincreased 1.8%, 7.47 % 15.23% in comparison with the control group, the protein level of PTEN was up-regulated accordingly, whereas the express of p-AKt was down-regulated. The caspase3 protein with apoptotic effect was activated.Conclusion:1. dMChR possess the significant inhibitory effect of the cell growth of human lever carcinoma cell (hepG2) in vitro, and it has less toxic activity on human embryo lever diploid cell(L-02). The toxic activity of the dMChR is highly selective to tumor cell in vitro.2. dMChR induced apoptosis of hepG2 cell line, and the action is associated with activication of PPARγ, up-regulation expresson of PTEN protein, down-regulation expresson of p-AKt protein and activation of Caspase3.