Effects of Irradiation on Cell Cycle and Expression of MDC1 and 53BP1 in Esophageal Carcinoma Cells

Objective To investigate changes of cell cycle, apoptosis and protein expression in esophageal carcinoma cells after 60Co γ-rays irradiation, it is the basis as combing target treatment and radiotherapy for esophageal cancer.Methods Using flow cytometry (FCM) to check the percentage of different phase cells and apoptosis at 1, 2, 12, 24, 48 h after irradiation (0,1,2,5,10,15Gy). Expression of MDC1 and 53BP1 were detected by Western blot after irradiation. Results The percentage of G0/G1, G2/M and S phase of TE-13 cells was changed dependence on doses increasing of irradiation. At 12 h after irradiation with 1 Gy and 2 Gy, arrest of G2/M stage was gradually increased and reached the peak at 24 h after irradiation with 5,10,15 Gy (P0.05). Apoptotic index of TE-13 cell was obviously elevated at 12 h,24 h and 48 h after irradiation with 15 Gy (P0.01). However, expression of MDC1 and 53BP1 proteins in TE-13 cells were no significant changes at 48 h after irradiation with 5,10,15 Gy (P0.05), compared with the control group. Conclusion G2/M arrest and apoptosis of TE-13 cells were remarkable increasing after different doses irradiation. Meanwhile, No changes of expression of MDC1 and 53BP1 proteins in TE-13 cells were investigated after irradiation.