Luciferase reporter assay
A luciferase reporter assay was conducted to assess the activity of the TP53BP2 promoter. For the promoter activity assay, various fragments of the TP53BP2 promoter (-35/+1, -599/+1, -1018/+1, -1530/+1, -599/+641, and -2000/+1) were inserted into the pGL3-Basic plasmid. The cells were then seeded in 24-well plates and cotransfected with the aforementioned reporter constructs and a Renilla luciferase reporter plasmid. Following a 48-hour transfection period, the luciferase activities were quantified via a dual-luciferase reporter assay system (Promega, Madison, USA). The firefly luciferase activity was determined and normalized to the Renilla luciferase activity. The reported data represent the average of three independent experiments.