Mechanism and clinical significance of cyclooxygenase-2 expression in gastric cancer

Table 1 Relationship between HpaII and HhaI demethylation, COX-2 expression and clinical parameters in gastric cancers.

	n	HpaII		HhaI		COX-2 expression
		D	M	D	M	+	-
Differentiation
High/moderate	21	18	3	19	2	16	5
Poor	23	16	7	18	5	14	9
TNM staging
I/II	13	8	5	9	4	6	7
	31	26	5	28	3	24	7a
Lymph node metastasis
No	17	11	6	12	5	8	9
Yes	27	23	4	25	2	22	5c

^aP <0.05 vs I/II stage group,

^cP<0.05 vs no LN metastasis group, D: demethylation, M: methylation.

Table 2 Correlation of HpaII and HhaI site demethylation and COX-2 expression.

COX-2 expression	HpaII		HhaI
	D	M	D	M
+	29	1	28	2
-	5	9b	9	5a

^aP<0.05 vs HhaI,

^bP<0.001 vs HpaII, D: demethylation, M: methylation.