Flow Cytometry Assay

ESCC cells were seeded in 6-well plates and divided into four groups: NC group (NC), shUHRF1 group (shUHRF1), NC + irradiation (NC + IR) group and shUHRF1+ irradiation group (shUHRF1 + IR). The IR groups received 6 Gy X-ray irradiation 24 h before detection. The apoptosis rate was measured following the instructions of the Annexin V-APC/7-AAD apoptosis detection kit (BD Biosciences, Franklin Lakes, NJ, USA). Briefly, the cells were resuspended in 500 μL binding buffer, mixed well after the addition of 5 μL Annexin V-APC, mixed well after the further addition of 5 μL 7-AAD, incubated at room temperature in the dark for 5–15 min, and analyzed by the FASC Calibur MT flow cytometer (BD Biosciences, Franklin Lakes, NJ, USA).