Table 1.

Colony formation assay

	500 ng of plasmid		10 ng of plasmid
	Number of colonies*	% inhibition	Number of colonies*	% inhibition
Empty vector	403	0	511	0
FLAGp53	65	84	433	15
FLAGp53-GA25/C	9	98	281	45
FLAGp53-GA239/C	49	88	241	53

U20S cells were transfected with 500 or 10 ng of the indicated plasmids. After overnight recovery, the cells were split into duplicate wells of a 24-well plate (≈8,000 cells per well) and grown for 2 weeks in the presence of 0.5 mg/ml of Geneticin. The number of Geneticin-resistant colonies and the percentage of p53-induced inhibition compared to the empty vector control are indicated. 

^*Mean of duplicates. One representative experiment of three performed by transfecting 500 ng of plasmids and one performed with 10 ng of plasmid are shown.