Synthesis of novel gold nanoparticles and its radiosensitizing effect on HepG2 cells / 中华放射医学与防护杂志

ABSTRACT

Objective To synthesize novel gold nanoparticles of GAL-PEG-GNPs,study its radiation effect on hepatocellular carcinoma cells HepG2 cells in vitro,and investigate the underlying mechanisms.Methods GAL-PEG-GNPs were synthesized and characterized successfully.HepG2 cells were divided into three groups of control,GNPs and GAL-PEG-GNPs.The cytotoxicities of these compounds were tested by the CCK-8 assay and their IC50 values of HepG2 cells were calculated.Cell uptake of nanoparticles was detected by TEM and ICP-MS.The radiosensitization effect of nanoparticles was tested by the colony formation assay.Cell cycle distribution was detected by FCM.The expressions of CAT,SOD,and total GSH were detected with a microplate reader,and the expressions of apoptosis-related proteins were tested by Western blot.Results The GNPs and GAL-PEG-GNPs had absorption peaks at 520 and 530 nm,respectively,and their diameters were (22.6-±2.12) and (32.0 ± 1.41) nm detected by ICP-MS.The GAL-PEG-GNPs and GNPs had similar cytotoxicity profiles (P ＞ 0.05),while GAL-PEG-GNPs could be more effectively uptaken by HepG2 cells than GNPs.The sensitive enhancement ratio (SER) of GNPs and GAL-PEG-GNPs to HepG2 cells were 1.46 和 1.95,respectively.The percentage of cells at phase of G2/M in HepG2 population treated with GNP was higher than that of untreated cells (t =14.20,P ＜0.05).The protein expressions of Cytochrome C,Bax,Caspase-3,and Caspase-9 were upregulated while Bcl-2 expression was down-regulated in the cells treated with GNPs/radiation or GAL-PEGGNPs/radiation.The expressions of CAT,SOD and total GSH in the GNP treated groups were significantly decreased compared with the control group(t =12.34,29.39,12.85,P ＜ 0.05).Conclusions GALPEG-GNPs has obvious radiosensitization effect on HepG2 cells,which is related to the induction of cell apoptosis and the generation of free radicals.