Figure 3.

Treatment of H1299 lung carcinoma cells with CP-31398 provokes massive cell death and p53 independent decline of luciferase reporter gene activity. (A) H1299 cells were transfected with expression constructs for wild type p53 (lanes 1–3) and p53V173A (lanes 4–6). All the samples were cotransfected with a p53-responsive luciferase reporter (p21 luciferase, containing a single p53 responsive p53 binding site from the human p21 promoter, termed WWP-luc, see material and methods) and a constitutive reference β-galactosidase construct (CMV-lacZ) for normalization. These cells were subsequently incubated with 0, 10, 15 μg/ml CP-31398 respectively and relative luciferase activities were determined. (B) H1299 cells were transfected with an expression construct for the synthetic activator GAL4-VP16. All samples were cotransfected with a gal4p responsive luciferase reporter (UAS_G luciferase) and a reference β-galactosidase plasmid (CMV-lacZ) for normalization. The control cells were transfected with CMV-lacZ and UAS_G luciferase only. These cells were subsequently incubated with 0, 10 and 15 μg/ml CP-31398 and relative luciferase activities were determined. The cells were treated with CP-31398 for 16 hours.