Enhancement Of Ratiation Effect On Lungcancer A549 Cells By Gold Nanoparticles

Background Lung cancer is a malignant tumor with a high incidence in the world.Its mortality rate is the highest among all malignant tumors.The main cause of death is uncontrolled local tumor,recurrence,and metastasis.Radiotherapy plays an important role in the treatment of lung cancer.However,lung adenocarcinoma is less sensitive to radiation therapy,and normal tissue tolerance and toxic side effects limit the efficacy of radiotherapy.Glucosecoupled gold nanoparticles(Glu-GNPs)as a novel sensitizer can not only increase the radiosensitivity of lung cancer,but also decrease the toxicity of surrounding tissues,which can effectively improve the response of lung adenocarcinoma to radiation therapy and prolong the survival period of lung cancer patients.Objective To study the in vitro radiosensitization effect of Thio-glucose capped gold nanoparticles(Glu-GNPs)combined with kilovolt or megavoltage X-ray on lung adenocarcinoma A549 cells.Methods The crystal violet method was used to detect the cytotoxicity ofGlu-GNPs on A549 cells and the radiosensitive inhibition of proliferation.The distribution of Glu-GNPs in the cells was observed by transmission electron microscopy(TEM).Dose-cell viability scores after irradiation with 160 KeV and 6 MeV X-rays,respectively,were determined by cell clone analysis and radio-biological parameters were calculated using a single-click multi-target model.The DNA double-strand breaks(Foci)of A549 cells were detected by ?-H2 AX immunofluorescence.Results TEM showed Glu-GNPs into A549 cells were aggregated state attached to intracellular membrane organelles-lysosomes or endosomes.GluGNPs at the concentration of 0-100 nmol / L did not significantly inhibit the viability of A549 cells(P> 0.05).Cell cloning experiments showed that the SER of 100 nmol / L Glu-GNPs combined with 160 KV and 6 MeV irradiation was1.41 and 1.15,respectively(P <0.05).Glu-GNPs significantly increased DNA double-strand breaks in A549 cells induced by 160 KV and 6 MeV X-rays(P<0.05).Conclusion Nano-gold can enter cells by endocytosis and locate in endosomes or lysosomes,and increase the sensitivity of lung adenocarcinoma A549 cells to radiation.