Table 2.

Methylation levels of 15 genes from pairs of normal and malignant breast tissues

Gene	Number of cases studied	Methylation level (mean ± SD) (Positive rate*)
		Normal	Cancer	pvalue**
LINE1	90	68 ± 4	60 ± 9	< 0.001
RIL	90	10 ± 4 (4.5)	27 ± 22 (57)	< 0.001
HIN-1	90	5 ± 3 (2.3)	20 ± 20 (49)	< 0.001
RASFF1A	90	3 ± 3 (3.4)	19 ± 20 (58)	< 0.001
CDH13	90	3 ± 2 (0)	14 ± 13 (44)	< 0.001
RARβ2	90	2 ± 1 (0)	7 ± 12 (17)	< 0.001
ARHI CpG I	32	30 ± 6 (0)	47 ± 16 (49)	< 0.001
ARHI CpG II	32	38 ± 7 (2)	36 ± 10 (2)	0.250
RIZ1	37	2 ± 2 (0)	3 ± 4 (5)	0.111
E-cadherin	34	4 ± 3 (3)	4 ± 4 (9)	0.163
p16	33	2 ± 1 (0)	1 ± 1 (0)	0.044
hMLH1	33	2 ± 3 (6)	1 ± 1 (0)	0.864
14-3-3 σ	10	75 ± 21	60 ± 28	0.275
NKD2	47	2 ± 4 (2)	4 ± 7 (8.5)	0.308
PGRB	48	3 ± 2 (0)	2 ± 3 (0)	0.594
ERα	40	7 ± 4 (3)	5 ± 3 (5)	< 0.001

*Positive rate using the sample mean plus two times the SD of the pooled normal samples (and minimum 10% methylation) as a cut-off point.

**p value computed using the Wilcoxon signed rank test for paired data. SD, standard deviation.