Methylation of PTCH1a gene in a subset of gastric cancers

Table 1 Primers and size of PCR products

Methods	Primers	Sequence	Length (bp)
QRT-PCR	PTCH1	5'-TGTGCGCTGTCTTCCTTCTG-3'	119
		5'-ACGGCACTGAGCTTGATTC-3'
	β-actin	5'-GCCATCCTGCGTCG-3'	260
		5'-TGGGCACCGGAACCGCT-3'
BSP		5'-GGGAGTATTTGGGTGGTATATT-3'	351
		5'-AAAAAACTACAAAAAAACACCACCTTTC-3'
MSP	Methylation	5'-GAGGGATCGATACGAATTC-3'	143
		5'-GAAAACGCGAAAAAACTAAA-3'
	Non-methylation	5'-GAGGGATTGATATGAATTT-3'	143
		5'-AAAAACACAAAAAAACTAAA-3'

QRT-PCR: Quantitative PCR.

Table 2 Clinical features in relation to methylation of PTCH1a TRR in gastric cancer

Variable	PTCH1methylation
	n	Positive	Negative	P value
Total	170	55	115
Clinicopathological parameters
Sex
Male	89	26	63	0.359
Female	81	29	52
Age of onset (yr)
< 50	68	22	46	1.000
≥ 50	102	33	69
Clinical stage
pT1	75	25	50	0.808
pT2-4	95	30	65
Lymph node metastasis
pN0	55	16	39	0.530
pN1-3	115	39	76
Histological grade
Well and moderately differentiated	63	19	44	0.735
Poorly differentiated	107	36	71