TABLE 4.

Methylation levels in GC tissues.

	Methylation level of tumor sample (mean ± SD)	P*	Methylation level of normal sample (mean ± SD)	P*
Gender
Male	0.11 ± 0.11	0.936	0.07 ± 0.10	0.857
Female	0.10 ± 0.11		0.07 ± 0.08
Age (year)
<65	0.12 ± 0.12	0.688	0.07 ± 0.08	0.109
≥65	0.10 ± 0.11		0.08 ± 0.12
TNMstage
T1, T2	0.11 ± 0.10	0.473	0.09 ± 0.12	0.034
T3, T4	0.10 ± 0.12		0.07 ± 0.09
Vessel invasion
Negative	0.10 ± 0.11	0.811	0.08 ± 0.10	0.147
Positive	0.11 ± 0.14		0.06 ± 0.07
Lauren type
Intestinal	0.10 ± 0.10	0.011 (For intestinal versus diffuse P = 0.009)**	0.07 ± 0.10	0.154
Diffuse	0.16 ± 0.22		0.09 ± 0.09
Mix type	0.12 ± 0.12		0.08 ± 0.09
Differentiation
Poor	0.11 ± 0.11	0.0164 (For poor versus well P = 0.023)**	0.08 ± 0.08	0.073
Moderate	0.09 ± 0.10		0.07 ± 0.13
Well	0.08 ± 0.14		0.05 ± 0.06

*Calculated by using independent samples t-test for two groups of data and using one-way ANOVA for three groups of data. **Compared by using lsd method for two of three groups.