Radiosensitization effect of low-temperature plasma on human malignant cells / 中华放射医学与防护杂志

ABSTRACT

Objective To evaluate the radiosensitization effect of low-temperature plasma on HepG2, A549, and HeLa cells.Methods Cells were divided into three groups, radiation group (R) , plasma treatment group(P), and plasma plus radiation group (P + R).After radiation, cell survival was detected by a cloning assay.Cell cycle distribution, apoptosis and ROS content were tested by flow cytometry.Western blot was used to measure the expressions of Caspase-3 and Bcl-2.Results Lowtemperature plasma showed radiosensitization effects on three different human malignant cell lines with a sensitivity enhancement ratio(SERD0) of 1.28,1.32 and 1.29.respectively.In these three different human malignant cell lines, compared with radiation alone group (R) , the G2/M arrest, apoptosis rate and ROS level in the group P + R were enhanced (the prolongation of G2/M arrest t =9.52, 8.24, 9.53, P ＜ 0.05;the apoptosis rate t =10.67, 38.56, 6.74, P ＜0.05;ROS content t =9.41, 15.42, 13.53, P ＜0.05).In HepG2 cells and A549 cells, compared with group P, the prolongation of G2/M arrest, the apoptosis rate and ROS content of group P + R were enhanced (the prolongation of G2/M arrest t =8.75, 20.37, P＜0.05;the apoptosis rate t =8.43, 9.99, P ＜0.05;ROS content t =4.82, 5.27, P ＜ 0.05).The expression level of Bcl-2 protein was downregulated in group P + R;by contrast, the expression level of Caspase-3 protein in group P + R was upregulated.Conclusions Low-temperature plasma can increase the radiosensitization of HepG2, A549 and HeLa cells with the enhancement of G2/M phase arrest, apoptosis induction and ROS generation.