Loss of heterozygosity on 10q23.3 and mutation of tumor suppressor gene PTEN in gastric cancer and precancerous lesions

Table 1 Primers of PTEN microsatellite loci and exons.

Loci	Position	Primer sequence
D10S215	10q22-23	P1 TGGCATCATTCTGGGGA
		P2 TTACGTTTCTTCACATGGT
D10S541	10q22-23	P1 AAGCAAGTGAAGTCTTAGAACCACC
		P2 CCACAAGTAACAGAAAGCCTGTCTC
D10S2491	10q23-23	P1 TTATAAGGACTGAGTGAGGGA
		P2 GTTAGATAGAGTACCTGCACTC
Exon 5		P1 CTTATTCTGAGGTTATCTTTTTTACC
		P2 CTCAGAATCCAGGAAGAGGA
Exon 8		P1 ACACATCACATACATACAAGTC
		P2 GTGCAGATAATGACAAGGAATA

Table 2 PTEN LOH in gastric cancer and precancerous lesion.

Lesions	D10S215 % (n)	D10S541 % (n)	D10S2491 % (n)	Total %
AG	3.3 (1/30)	3.3 (1/30)	6.7 (2/30)	10
IM	3.3 (1/30)	3.3 (1/30)	3.3 (1/30)	10
AH	6.7 (2/30)	3.3 (1/30)	6.7 (2/30)	13.3
Gastric cancer
Early stage	6.7 (2/30)	10 (3/30)	6.7 (2/30)	20
Advanced stage	13.3 (4/30)	6.7 (2/30)	13.3 (4/30)	30

AG: atrophic gastritis; IM: intestinal metaplasia; AH: atypical hyperplasia.

Table 3 Mutation of PTEN in gastric cancer.

Case	Exon	LOH	Coden	Base change	Stage	Pathology
11	5	+	91	GAA to CAA	IIIa	Signet-ring cell cancer
19	8	+	335	CGA to TGA	II	Hypodifferentiated adenocarcinoma
22	8	+	329	Del 4 bp	IIIb	Undifferentiate gastric cancer