Role of caspase-3 played in As_4S_4 induced apoptosis of Hela cell line

Objective To investigate the possible role of caspase-3 and bcl-2 played in As_4S_4 induced apoptosis of cervical tumor Hela cell line.Method Hela cells were cultured with various concentrations(7.5,15,30 and 60 mg/L)of As_4S_4 for 12,24,36,48 and 60 h respectively,then measuring the situation of cell growth apoptosis with MTT and flow cytometry analysis.The expressions of(bcl-2) and caspase-3 protein were detected by Western blot,caspase-3 activity was evaluated with flow cytometry.Result The results showed that As_4S_4 might time and dose dependently depress the proliferation of cervical tumor Hela cell line significantly,the IC_(50) for 24 h was 30 mg/L.Flow cytometry revealed after 24 h co-culture the apoptotic rates of Hela cells were(8.13±1.13)%、(29.58±2.51)%、(46.24±3.92)% and(62.36±4.42)%,respectively(P0.01),under different concentrations of As_4S_4(7.5,15,30,60 mg/L),while the apoptotic peak did not appear in control group(P0.01).The expression of bcl-2 protein was also down-regulated;while caspase-3 protein was up-regulated with the increase of dose,(2.67±0.22)%,(9.53±0.15)%,(21.28±0.43)%,(39.63±0.80)% and(63.40±0.69)%,respectively(P0.01).Conclusion As_4S_4 has the effect of depressing proliferation and enhancing apoptosis on Hela cell in vitro,its mechanism may related to down-regulating the expression of bcl-2 protein and activating the activity of caspase-3.