Microsatellite instability in oral cancer

Abstract

Generalized genomic instability, detected as somatic changes in allele sizes at microsatellite loci in tumors compared to peripheral lymphocyte DNA, is a recently recognized mechanism of mutation in cancer. Such instability results from the somatic loss of DNA mismatch repair capability. Germ-line mutations at DNA mismatch repair loci confer susceptibility to colon cancer in hereditary non-polyposis colorectal cancer. Somatic loss of DNA mismatch repair has been reported in a large variety of other tumor types. Our goal was to determine the frequency of microsatellite instability in a large series of oral tumors. Out of 91 tumors analyzed for microsatellite instability, 6 (7%) showed microsatellite instability. Instability was observed at multiple loci with a range of 50-74% of loci affected. Alterations include both increase (74%) and decrease (26%) in allele sizes. The proportion of alleles affected ranged from 30-58% of all alleles. Our data suggest that somatic genomic instability plays a role in the pathogenesis of a small subset of oral tumors.

Microsatellite instability in squamous cell carcinoma of head and neck from the Indian patient population

“…25 Another study reported only 7% SCCHN with MIN; all of them exhibited instability at 40% or more loci. 35 In a French study only 1 tumor exhibited high MIN type, and 6 tumors were classified as low MIN type out of 56 tumors analyzed. 27 Thus SCCHN tumors from Indian patients show much higher MIN frequency than patients from other populations.…”

Towards a simple, saliva-based test for the detection of oral cancer.

“…However, none of these markers universally identifies OSCC. Microsatellite markers are the most promising amongst these, where at least one of a panel of 23 markers can detect the presence of an oral cancer cell in the saliva of 79% of oral cancer patients [16][17][18][19]. However, microsatellite instability analysis is not particularly sensitive and requires large amounts of cancer cell DNA, approximately one cancer cell among 200 normal cells.…”

Molekularzytogenetische Charakterisierung von Plattenepithelkarzinomen des Kopf-Hals-Bereiches

“…Åkervall et al (1995) Chromosomen 3p, 5q, 9p, 9q, 11p, 13q, 17q und 18q festgestellt (Ah-See et al, 1994;Bockmühl et al, 1996a;Field et al, 1995a;Ishwad et al, 1995;Scully & Field 1997). Li et al (1994) Reed et al, 1996).…”