Arsenic trioxide induced human cervical cancer cell apoptosis and effect of bcl 2 overexpression on it

Lipofectin mediated DNA transfection, MTT reduction, clone forming assay, flowcytometric analysis and in situ cell death detection were used to study the biological effect of As 2O 3 on human cervical cancer SiHa and HeLa cells and the protection by bcl 2. The results showed that the survival and clone forming rate of SiHa and HeLa cells were decreased by treatment of As 2O 3. The cells showed hypodiploid peak before G 1 phase and were blocked in G 2/M phase as well as DNA fragmentation. Compared to their material cells, the survival rate of As 2O 3 treated SiHa and HeLa cells with bcl 2 overexpression was increased while apoptotic rate was decreased as well as the G 2/M arrest of the cells was partly reversed. The results suggest that As 2O 3 induces apoptosis of SiHa and HeLa cells possibly via inducing G 2/M arrest; overexpression of bcl 2 partly inhibits As 2O 3 induced apoptosis, which is related to prevent the cells from As 2O 3 caused G 2/M block.