| Objective To study the effect of cantharidin on radiotherapy sensitization of A-549 cells of non-small cell lung cancer（NSCLC）in vitro.Methods The proliferation inhibition of cantharidin on A-549 cells at different concentrations and at different times was determined by CCK8.The combined effect of cantharidin and radiation was analyzed in the clone formation experiment,and the curve fitting was carried out using the single-click mμlti-target model to obtain the cell survival curve,the mean lethal dose,the quasi-threshold dose,the radiation sensitization ratio and other parameters.Flow cytometry was used to analyze the cell cycle and apoptosis rate of cantharidin combined with radiation on A-549 cells.Western blot was used to detect the contents of apoptosis-related proteins bcl-2 and Bax between cantharidin and radiotherapy groups,and to preliminarily investigate the mechanism of cantharidin increasing radiotherapy sensitivity.Resμlts 1.CCK8 method was used to demonstrate that cantharidin had A growth inhibition effect on A-549 cells in A time and dose-dependent manner,with IC50 of3.113μg/ml and IC20 of 0.362μg/ml for 24 hours.2.By observing the cell status in the blank group,cantharidin group and cantharidin plus radiotherapy group,it can be seen that both cantharidin and radiation can cause cell apoptosis.3.Clone formation experiments show that cantharidin and radiation can reduce the cloning rate of A-549 cells,and the cloning formation rate of the radiotherapy combined with cantharidin group was the lowest,Dq and D0 were lower than the radiotherapy alone group,and SER was 1.262,statistically significant differences（P<0.05）.indicating that cantharidin coμld enhance the killing effect of radiation on lung cancer A-549 cells.At the same time,it was proved that the apoptosis of lung cancer A-549 cells increased significantly with the increase of radiation dose at the same drμg concentration.4.Cell cycle and apoptosis rate of cells in each treatment group showed that the proportion of G2/M cells in the cantharidin+radiotherapy group was significantly higher than that in other groups,with statistically significant differences（P<0.05）.The apoptosis rate of cantharidin group combined with radiotherapy was significantly higher than other groups,and the difference was also statistically significant（P<0.05）.5.Western blot detection of apoptosis-related proteins Bcl-2 and Bax showed that Bcl-2 protein was significantly reduced and Bax protein was significantly increased in the cantharidin combined with radiotherapy group,and the difference was statistically significant compared with other groups（P<0.05）.Conclusion1.cantharidin can inhibit the proliferation of lung adenocarcinoma A-549 cells in vitro.2.cantharidin had a radiosensitizing effect on lung adenocarcinoma A-549 cells cμltured in vitro.3.The mechanism of cantharidin increasing the radiotherapy sensitivity of lung adenocarcinoma A-549 cells may be to block cell cycle and induce apoptosis. |
