The Experimental Study In Vitro Of Aresenic Trioxido For Increasing Radiosensitivity In A₅₄₉ Human Lung Adenocarcinoma Cell Lines

[Objective] To evaluate the radiosensitive effect of Arsenic trioxide(As2O3) on the A549 human lung adenocarcinoma cell line in vitro. [Methods] The methods of MTT and FCM were used to analysis the cell cytotoxics in the different groups of A549 cell line with AS2O3 concentration of 0 μmol/L, 1μmol/L, 2μmol/L, 2.5μmol/L and 5μmol/L combined with irradiated of 1Gy, 3Gy, 5Gy, 7 Gy and 9Gy within 24 to 48 hours after incubation with AS2O3 and in the groups of A549 cell lines with irradiation alone. The cell survival curves were determined by cloning assay for evaluating the cell killing effects in the groups of irradiation plus AS2O3 and the groups of irradiation alone.[Results] It was shown that the intensities of cell proliferating inhibition seemed to be much dependent on increasing of AS2O3 concentration.The cell survival rates were lower in the combination groups than those in the groups of irradiation alone.The D0 and Dq values decreased significantly in the combination groups with the values of l.lGy, 0.99Gy, 0.91Gy, 0.56Gy and 1.717Gy, 1.578Gy, 1.419Gy ,0.874Gy respectively at the AS2O3 concentration levels of 1μmol/L, 2μmol/L, 2.5μmol/L and 5μmol/L respectively compared to those in the groups of irradiation alone.The radiation enhancement ratios were 1.136, 1.263, 1.374 and 2.230 respectively at the same levels of AS2O3 concentration in the combination groups.Flow cytometric analysis indicated that AS2O3 induced G2/M phase arrest obviously in the cell cycle of the A549 cell lines 24 hours after irradiation exposure.[Conclusion] It was concluded that AS2O3 might be a potential radiosensitizer for the further study of human lung adenocarcinoma in vitro.