Effects of CDT1 gene over-expression on cell apoptosis and cell cycle in irradiation-induced genomic instable liver cells

Abstract

Objective To investigate the effect of CDT1 gene over-expression on the apoptosis and cell cycle distribution in liver cells with a characteristic of genomic instability induced by radiation(GIR). Methods Lentivirus particles were transferred into liver cells of GIR to up-regulate the expression of CDT1 gene. The apoptosis and the cell cycle were detected by flow cytometry (FCM). The expression changes of p53, ATM, ATR, Bcl-2, and Caspase-3 genes were analyzed by real-time fluorescence quantitative PCR. Results CDT1 gene was efficiently increased by the gene transfection(t=15.56, P<0.05). In the CDT1 over-expressed cells, while the apoptosis ratio was increased(t=4.19, P<0.05), the expressions of p53 and Bcl-2 gene were decreased (t=-4.21, -2.06, P<0.05), but the expression of ATM, ATR and Caspase-3 changed with no significant difference compared with control. Conclusions Over-expression of CDT1 could regulate genomic instability through apoptosis pathway and checkpoint independent of p53. Key words: CDT1; Genomic instability; Over-expression; Cell cycle; Cell apoptosis