Methylation of GATA-4 and GATA-5 and development of sporadic gastric carcinomas

Table 1 Comparison of GATA-4 and GATA-5 methylation status with clinicopathological characteristics of SGC

Clinicopathological characteristics	Methylation positive rate (%)
	GATA-4		GATA-5
	SGC	N	SGC	N
SGC invasion
T1&T2 (n = 20)	45.0a	35.0b	45.0	45.0
T3 (n = 50)	54.0	42.0	68.0	48.0
T4 (n = 10)	70.0	50.0	60.0	40.0
Metastasis
Yes (n = 44)	52.3	31.8	61.4	36.4
No (n = 36)	55.6	52.8	61.1	38.9
H. pylori infection
Positive (n = 42)	61.9	45.2	64.3	50.0
Negative (n = 34)	41.2	38.2	55.9	44.1
Age (yr)
≤ 59 (n = 42)	45.2	33.3	57.1	28.6
≥ 60 (n = 38)	63.2	50.0	65.8	65.8c
Sex
Male (n = 62)	51.6	41.9	61.3	51.6
Female (n = 18)	61.1	38.9	61.1	27.6d
Total
n = 80	53.8	41.3	61.3	46.3e

SGC: Sporadic gastric carcinomas; N: Adjacent corresponding non-neoplastic gastric tissue; H. pylori: Helicobacter pylori detected by the 23S rRNA-PCR assay[16]; ^a,bAnalysis for linear trend by EpiInfo 6.0 software, positive rates vs extent of penetration of the stomach wall, P = 0.198 and 0.434, respectively;

^cχ² test by EpiInfo 6.0 software, samples from young patients (≤ 59 years old) vs old patients (≥ 60 years old), P < 0.001;

^dMale vs female, P = 0.074;

^eSGCs vs the normal, P = 0.057.

Table 2 GATA-4 and GATA-5 methylation frequency (%) in gastric dysplasia lesions in subjects from Linqu County, a high risk area for stomach cancer

Classification of gastric dysplasia	GATA-4	GATA-5
Low-grade noninvasive neoplasia	57.1 (16/28)	69.0 (20/29)
Hp-infection
With	71.4 (15/21)	63.6 (14/22)
Without	14.3 (1/7)a	85.7 (6/7)
Indefinite for dysplasiab	42.9 (30/70)	46.7 (35/75)c
Total	46.9 (46/98)	52.9 (55/104)

^aχ² test by EpiInfo 6.0 software, with vs without Hp-infection, P = 0.023;

^bOnly two cases without Hp-infection;

^cχ² test by EpiInfo 6.0 software, Low-grade noninvasive neoplasia (GIN) vs indefinite for dysplasia, P = 0.042.

Table 3 Correlation of the GATA-4 and GATA-5 methylation status with their protein expression in sporadic gastric carcinomas with IHC

Protein expression, by IHC	GATA-4 methylation status			GATA-5 methylation status
	M	U	P-valuea	M	U	P-value
Positive (+ ~ +++)	7	11	0.012	5	9	0.011
Negative (- ~ ±)	11	3		16	3

IHC: Immunohistochemical staining; +~+++: 10% or more cancer cells exhibited a similar positive staining pattern; - or weak: Positive expression in less than 10% cancer cells or a weak staining pattern compared with a non-cancerous area of the same section; M: Methylated; U: Unmethylated;

^aFisher’s exact test by EpiInfo 6.0 software.