Effects Of As₂O₃ Combined With AZT On Migration And Invasion Of Hepatoma HepG2 Cells

Objective: To investigate the effects of arsenic trioxide（As₂O₃） combined with3’-azido-3’-deoxythymidine（AZT） on the migration and invasion of human hepatoma HepG2 cells and its possible mechanism. In support of experiment information for further in vivo study and clinical treatment against hepatoma.Methods: Human hepatocelluar carcinoma HepG2 cells were cultured in vitro. The migration and invasion of the cells were measured by wound healing assay, transwell migration and invasion assay after treatment with As₂O₃, AZT and their combination,respectively. The expression levels of MMP2 and VEGF mRNAs after treatment with As₂O₃,AZT and their combination were analyzed through quantitative Real-time PCR（qPCR）.Western blotting was used to examine the expression levels of MMP2、VEGF、ERK1/2 and p-ERK1/2 proteins.Human liver cells HL-7702 were cultured in vitro. The expression levels of PTK6 mRNA in HL-7702 cells and HepG2 cells were analyzed through qPCR. Moreover, we examined the levels of PTK6 mRNAs in HepG2 cells after treatment with As₂O₃, AZT and their combination.Result: The result of wound healing assay indicated a significant decrease of migration ability in combination group than control group and As₂O₃ or AZT alone groups（P<0.01）. A significant decrease was observed in the number of HepG2 cells per field permeating the artificial membrane in the combination group, compared with the control group and As₂O₃ or AZT alone groups（P<0.01） by means of transwell migration and invasion assay. As compared with the control, As₂O₃ and AZT alone groups, the mRNA expression levels of VEGF and MMP2 in As₂O₃ combined with AZT group were down-regulated（all P<0.01）, as well as the protein expression levels of MMP2, VEGF and p-ERK1/2 were also down-regulated（all P<0.01）; but there was no obvious change in expression of ERK1/2protein among four groups（P>0.05）.The result of qPCR indicated a significant decrease of PTK6 mRNA in HepG2 cells than HL-7702 cells（P<0.01）. Moreover, the expression levels of PTK6 mRNA in HepG2 cells wasup-regrulated after treatment with As₂O₃, AZT and their combination（P<0.01）.Conclusion: As₂O₃ combination with AZT has synergistic effects on the migration and invasion inhibition in HepG2 cells. The effect may be associated with phosphorylation of ERK1/2 signal pathway and down-regulating the mRNA and protein expression levels of VEGF and MMP2. PTK6 maybe plays a role on the migration and invasion of HepG2 cells and further study is needed.