Toxicity,Cell-cycle Regulation And DNA Damage Of FePt Nanoparticles To A549 Cells In Chemoradiotherapy

The innovations in nanotechnology bring a brand-new prospect for tumor therapy.In this study,we synthesized a 3.1 nm FePt nanoparticles(NPs)of face-centered cubic stucture by a chemical reduction method.The characterization of FePt was via techniques of transmission electron microscopy(TEM),D8 X-ray diffractometer(XRD),Fourier transform infrared spectrometer(FTIR),X-ray photoelectron spectrometer(XPS)and ultraviolet spectrophotometer(UV).With cysteamine(Cys)remodified,the sensitivity of FePt NPs was evaluated by CCK-8 assay in A549(human lung adenocarcinoma cells)and HeLa cells(human cervical cancer cells)at different concentrations.Then,clonogenic assay was carried out in both cell lines at different doses to investigate the inhibiting ability of NPs in cell proliferation,combined with 6 MV X-ray irradiation.At last,to explore the detailed cytotoxic mechanisms of FePt NPs,cell-cycle redistribution assay and immunofluorescence assay of DNA double-strand breaks(DSBs)damage were conducted in A549 cells.Our results indicate that FePt NPs could induce remarkable cytotoxicity in both cell lines in vitro,no matter with or without irradiation.In addition,the cytotoxicity was in both time and concentration dependence.Furthermore,it was found that the inhibiting effect might be caused by cell-cycle down-regulated in G2/M phase and added DSBs damage of DNA.When X-rays was present,the effect would be obviously enhanced.Therefore,our cysteamine decorated FePt NPs could serve as a potential sensitizer in improving future chemoradiotherapy of cancer.