TABLE 1.

Cell cycle distribution of HIp53 cells after IR

DNA content or cell cycle phase	Time after IR treatment (h)	% of cells after IRa at:
		8 Gy		12 Gy		20 Gy		30 Gy
		−	+	−	+	−	+	−	+
<2 N DNA	15	13		0		2		1
G1	15	25		29		10		17
S	15	8		20		13		46
G2/M	15	54		51		75		36
<2 N DNA	24	20	13	0	0	4	5	5	7
G1	24	43	59	50	51	15	23	5	9
S	24	17	8	7	5	13	12	10	8
G2/M	24	20	20	43	44	68	60	80	76
<2 N DNA	48	21	13	11	4	31	9	16	10
G1	48	41	60	34	50	10	18	6	9
S	48	17	8	15	6	18	10	20	9
G2/M	48	21	20	40	40	41b	63	58b	72
<2 N DNA	72	22	14	5		42	11	57	11
G1	72	44	57	54	53	10	16	5	6
S	72	15	10	12	7	12	10	15	7
G2/M	72	19	19	29	40	36b	63	23b	76

^aResults are representative of two independent experiments. Values for a control, untreated culture were as follows: <2 N, 0%; G₁, 66%; S, 15%; G₂/M, 19%. − and +, absence and presence of PonA (plus p53), respectively. 

^bMore than 75% of the cells underwent cell death and detached from the plate; the number is representative of the remaining cells (see Fig. 2A).