APPLICATION OF THE SINGLE CELL GEL ELECTROPHORESIS IN THE DETECTION OF DNA DAMAGE AND APOPTOSIS

Cell nuclear DNA was broken into different fragments when it was damaged. During the alkaline gel electrophoresis, these fragments migrated far away from cell nucleus and showed comet shape due to different migration speed. The fluorescence intensity and length of comet tail had positive correlation with the degree of nuclear DNA damage. The single cell gel electrophoresis (SCGE) was performed to detect the comet proportion, the fluorescence intensity and length of comet tail after Hela cells were treated for 24 hours by different concentrations of three kinds of anticancer drugs, mitomycin C (MMC), carboplatin and 5-fluorouracil (5-Fu), and the feasibility of SCGE in the detection of apoptosis was investigated. The results showed that all of the treated groups showed comets after SCGE. The comet proportion increased as the concentration of drug increased, and so did the fluorescence intensity and length of comet tail. There was good dose-response relationships in each drug and the differences between different groups were significant (P0.05). These results indicated that all of three kinds of anticancer drugs induce the nuclear DNA damage in Hela cells, and SCEG can be used as a simple, rapid and sensitive method to detect DNA damage and cell apoptosis.