Effects of 12C heavy ion and γ ray irradiation in cell growth, cell cycle and apoptosis of human peripheral blood lymphocytes

Abstract

Objective To compare the effects of carbon heavy ion and γ ray on cell survival, cell cycle and cell apoptosis. Methods Peng-EBV cells were irradiated by carbon heavy ion and X-ray. MTS was used to detect the cell survival. Cell cycle and apoptosis were analyzed by flow cytometry. Results The proliferation inhibition rate of Peng-EBV cell was significantly increased after 2.0 Gy heavy ion rays and γ rays. Compared with the control group, the cell proliferation inhibition rate difference was statistically significant after 2.0 Gy rays at 24 h, 48 h, 72 h (heavy rays: t=10.53, 4.11, 37.30, all P<0.05; γ rays: t=7.18, 8.26, 26.11, all P<0.05) . The cell proliferation inhibition rate showed a time-dependent increase, and reached its peak at 72 h after heavy ion rays, while the cell proliferation inhibition rate after γ ray reached its peak at 48 h, and then decreased. Compared with the control group, the apoptosis rate of Peng-EBV cell increased 7.92 and 13.41 times respectively at 12 h and 24 h after 2.0 Gy heavy ion rays (t=7.09, 4.13, both P<0.05) , while it was 2.43 and 5.64 times after 2.0 Gy γ rays (t=8.98, 20.52, P<0.05) . Compared with the control group, the G2/M phase arrest increased 5.11 and 11.77 times respectively at 12 h and 24 h after 2.0 Gy heavy ion rays (t=12.06, 100.08, both P<0.05) , however, it was 5.82 and 7.68 times after 2.0 Gy γ rays (t=19.35, 10.30, both P<0.05) . Conclusion 12C heavy ion irradiation shows more stronger biological effects on human peripheral blood lymphocyte than γ ray. Key words: Heavy ions; Gamma rays; Lymphocytes; Radiation; Biological effect