The sensitization of gold nanoparticles on epirubicin

Abstract

Objectiye To observe the sensitization of gold nanoparticles on the epirubicin therapy of hepatocellular carcinoma cells (HepG2) and action mechanism. Methods The HepG2 cells were divided into 2 experimental groups: gold nanoparticles pretreatment group and simple epirubicin group. After seeded in a 96-well plate and cultured for 24 h, HepG2 cells were treated with 100 μl of gold nanoparticles (2 μg/L) and serum-free medium respectively. Then 100 μl of epirubicin ( 1 mg/L) was added to both groups at different time points: 30, 60, 120 and 240 min. The inhibition effect of epirubicin on the HepG2cells was assessed by methyl thiazol tetrazolium (MTT) assay. Ultraviolet-visible spectrophotometer (UV-Vis) was applied to detect the epirubicin accumulation in HepG2 cells at different time points, and atomic force microscope (AFM) was used to examine the ultrastructural changes of HepG2 cell surface. Results The inhibition rate of HepG2 cells in gold nanoparticles pretreatment group [(50. 53 ± 1.38 ) %,(51.83 ± 0. 47 ) %, (48. 66 ± 2.21 ) %, (43.55 ± 1.01 ) %] at different time points was higher than the simple epirubicin group remarkably [( 37.24 ± 3.49 ) %, ( 39. 42 ± 2. 28 ) %, ( 34. 98 ± 2. 27 ) %,(28.92 ±3. 80)%] ,P ＜0. 01. The gold nanoparticles pretreatment group (60 rain) had the maximal epirubicin accumulation: (4. 01 ±0. 14) μg. AFM revealed that when treated with gold nanoparticles, the morphologic changes of HepG2 cells were significantly different: there appeared invagination, obvious shrinked cell membrane and much rougher surface. Conclusion Gold nanoparticles can sensitize epirubicin through the enhancement of epirubicin accumulation in HepG2 cells. The pretreatment of gold nanoparticles for 60 min has the maximum sensitization. Key words: Gold nanoparticles; Epirubicin; Sensitization