twice, all adherent and floating cells were collected and lysed in RIPA Lysis
Buffer (Beijing ComWin Biotech Co., Ltd) for 20 minutes on ice. After
centrifugation at 12 000 rpm 4°C for 10 minutes, protein concentration was
determined using a Bicinchoninic Acid Assay Kit (Thermo Fisher Scientific, USA)
according to the manufacturer’s instructions. The same concentration of proteins
was separated by 12% SDS-PAGE and transferred to PVDF membranes. After washing
with PBST buffer (PBS with 0.05% Tween-20), the membranes were blocked with 5%
non-fat milk at 37°C for 1 hour, and then incubated with the primary antibodies
(Cell Signaling Technology, MA, USA) at proper dilutions overnight at 4°C. After
washing 3 times with PBST, the membrane was incubated with the corresponding
HRP-conjugated secondary antibodies (eBioscience) for 2 hours at 37°C. The
target proteins were detected using ECL assay kit (Beyotime). Grayscale scanning
data were obtained by Image J.