Cell viability assay
The cell viability assay was performed using the Cell Counting Kit-8
(Proteintech Group, Inc, USA). Briefly, the ESCC cells were seeded into
96-well plates at 6×103 cells/well and incubated under
standard culture conditions for 24 h, then the cells were treated with
gradient concentrations of ixazomib for 24-72 h. After treatment, 10 µl
of CCK-8 solution was added into each well of the 96-well plate and
incubated for 1 h at 37°C. The optical density (OD) values were detected
at 450 nm using a microplate reader (Biotek, Winooski, VT, USA). Each
experiment was independently repeated three times with five replicates.