Table 2.

BrdU incorporation in breast cancer and nonmalignant breast cells^*

Cell line		Breast cancer cells vs control MCF-10A			Breast cancer cells vs control MCF-10AT
	Mean percent of BrdU-positive cells relative to control	Difference	95% CI	P†	Difference	95% CI	P†	N
MCF-10A	125.30	—	—	—	—	—	—	4
MCF-10AT	94.30	30.99	−1.60 to 63.58	.06	—	—	—	8
MCF-7	46.96	78.33	32.80 to 123.9	.006	47.34	24.86 to 69.82	<.001	4
MDA-MB-231	56.22	69.07	24.42 to 113.7	.009	30.08	16.27 to 59.89	.003	4
SKBR3	78.16	47.13	3.33 to 90.93	.039	16.14	−5.02 to 37.30	.12	4
T47D	60.36	64.63	26.90 to 103.0	.005	33.94	14.71 to 53.17	.003	5
MDA-MB-453	71.84	53.45	.65 to 106.2	.048	22.46	−1.35 to 46.26	.062	3

^*Nonmalignant breast cell lines (MCF-10A or MCF-10AT) and breast cancer cell lines (MCF-7, MDA-MB-231, SKBR3, T47D, and MDA-MB-453) were treated with 6H5 mAb or mIgG (10 μg/mL per dose of each antibody) for 24 hours. The BrdU incorporation percentage of 6H5 mAb–treated vs mIgG-treated cells (control) was compared. A total of 5000 BrdU-positive cells were counted for each cell line. Mean values from at least three independent experiments are presented. BrdU = Bromodeoxyuridine; CI = confidence interval; mAb = monoclonal antibodies; N = number of independent experiments. — = not applicable.

^†P values reflect comparisons between MCF-10A cells and each breast cancer cell line, or between MCF-10AT cells and each breast cancer cell line, and were calculated using a two-sided Student's t test.