Influence of radiosensitivity by mild hyperthermia in a pulmonary adenocarcinoma cell line / 医学研究生学报

ABSTRACT

Objective:To investigate the radiosensitization and the cell-cycle of mild hyperthermia(≤42℃)on human pulmonary adenocarcinoma cell line SPC-A-1 in vitro. Methods: The human pulmonary adenocarcinoma cell line SPC-A were treated with radiation and the combination of radiation with mild hyperthermia. Radiosensitivity was determined by clonogenic assay and quantified by calculating the thermal enhancement ratio (TER). Flow cytometry was used to observe the cell-cycle. Results: Do, Dq calculated from the dose-response curve for radiation combined with 41.5℃ were 1.390 Gy, 1.426 Gy, whereas 1.693 Gy, 2.453 Gy for radiation alone, respectively. TER was 1.218. The proportion of cells in S phase was found to be 14.81% in the radiation group. The values, after 48 hours and 72 hours, with 6Gy radiation combined immediate 41.5℃ one hour mild hyperthermia, were 5.89% and 9.08%, respectively, versus 18.8% and 31.91% with 6 Gy radiation alone. Conclusion:Radiosensitization of mild hyperthermia in SPC-A-1 cells associated with the hyper-radiosensitization of the cells in S phase.