Immunofluorescence assay
MDA-MB-231 cells which were cultured on circular glasses in 24-well plates were exposed to different treatments. After that, cells were fixed with 4% paraformaldehyde for 10 min, incubated with permeabilization solution (1% Triton X-100) for 15 min, washed with cold PBS three times and blocked with 5% BSA solution for 1h. After incubated with primary antibodies overnight at 4 oC, cells were washed with cold PBS and incubated with FITC-conjugated goat anti-rabbit IgG secondary antibody (dilution, 1:500, Beyotime, Beijing, China) for 1 h at 37 oC. Finally, nucleus of MDA-MB-231 cells were stained with DAPI (dilution, 1:10000) for 10 min, and cell images were obtained by Laser Scanning Confocal Microscopy (Leica, German).