[Analysis of microsatellite regions and DNA ploidy pattern in signet ring cell carcinomas of the stomach].
We examined microsatellite instability (MSI) and loss of heterozygosity (LOH) in regions of several important genes in 25 signet-ring cell carcinomas of the stomach. The relationship between microsatellite analysis and DNA ploidy pattern was also investigated. MSI was observed in 15% (2/13) of early carcinomas and in 17% (2/12) of advanced carcinomas. Although LOH in the region of APC gene was found in 16% (4/25) and LOH of p53 was found in 12% (3/25), 15% (2/13) of early carcinomas and 33% (4/12) of advanced carcinomas showed LOH in regions of E-cadherin gene. Cyto-fluorometrical study revealed that 85% (11/13) of early carcinomas were diploid pattern, and aneuploid components were demonstrated in 50% (6/12) of advanced carcinomas. However, no MSI-positive cases contained aneuploid components, and in contrast, all p53-LOH cases contained aneuploid components. Our results suggest that gene abnormalities which have been frequently reported in differentiated adenocarcinomas are rare events in signet-ring cell carcinomas other than those associated with cell adhesion, and that MSI is not related to the occurrence of aneuploid cells.
Kimura
T
T
Dept. of Pathology, Shiga University of Medical Science.
Sato
H
H
Manabe
R
R
Konishi
H
H
Kushima
R
R
Sugihara
H
H
Hattori
T
T
Kodama
T
T
Kashima
K
K
D000328:Adult; D000368:Aged; D015820:Cadherins / Q000235:genetics; D018279:Carcinoma, Signet Ring Cell / Q000235:genetics*; D004273:DNA, Neoplasm / Q000235:genetics*; D005260:Female; D017491:Genes, APC; D016158:Genes, p53; D006579:Heterozygote; D006801:Humans; D008297:Male; D018895:Microsatellite Repeats; D008875:Middle Aged; D011003:Ploidies; D016133:Polymerase Chain Reaction; D013274:Stomach Neoplasms / Q000235:genetics*
D015820:Cadherins; D004273:DNA, Neoplasm