Assessment of microsatellite instability and loss of heterozygosity in sporadic keratoacanthomas

Abstract

Variations in the length of simple repetitive tandem repeats (microsatellite instability, MIN) between constitutive and tumour DNA, which is characteristic of tumours in patients affected with hereditary nonpolyposis colon cancer (HNPCC), have been found to be very important in the carcinogenesis of a variety of human neoplasms. Recently, MIN has been found in sebaceous and colorectal tumours as well as in keratoacanthomas of Muir-Torre syndrome. In order to elucidate the significance of both MIN and loss of heterozygosity (LOH) in the pathogenesis of sporadic keratoacanthomas, the presence of MIN and LOH at five loci [chromosome 5q21 (D5S346, APC), 9p21 (D9S171, p16), 10pter (D10S89, Mfd28), 11p (D11S904) and 17p12 (D17S520, p53)] was evaluated. MIN was found at only one locus (p53) in 1 of 12 keratoacanthomas and no evidence for the presence of LOH could be detected. Our results suggest that, in contrast to keratoacanthomas associated with Muir-Torre syndrome, neither MIN nor LOH appear to be significant in the induction of sporadic keratoacanthomas.

Analysis of Loss of Heterozygosity in Korean Patients with Keratoacanthoma

“…The APC tumor suppressor gene on chromosome 5 was analyzed because of its common involvement in gastrointestinal cancer (8). Our study and other two reports in keratoacanthoma (10, 11) could not detect LOH at D5S346, APC gene, suggesting that at this locus LOH may be not important in keratoacanthoma.…”

“…High frequencies of LOH in actinic keratoses appeared on 17p (64%), 17q (56%), 13q (60%), 9p (31%), 9q (44%), and 3p (26%), contrasting with their benign clinical course (23). In keratoacanthoma, Langenbach et al (11) observed not LOH but microsatellite instability at only D17S250 (p53) in 1 of 12 sporadic keratoacanthomas and Peris et al (10) detected genetic alternations at p53 locus in 2 patients showing LOH at D3S1317 of 20 keratoacanthomas. One patient with multiple kerathoacanthoma showed LOH at 17S261 and the other patient with a family history of visceral malignancies, putative case of Muir-Torre syndrome, had multiple microsatellite instabilities including those at D17S261 and D17S520.…”

Squamous cell carcinoma arising in a psoriatic nail bed: case report with discussion of diagnostic difficulties and therapeutic options

“…This underlines the value of attempted histological separation. A high degree of loss ofheterozygosity on chromosomal microsatellite analysis has been reported for VC recently, 30 and the converse has been reported in sporadic extra‐onychal KA, 31 but whether this will be a useful test in future for discriminating between VC and SUKA remains to beseen.…”

Topographical distribution of allelic loss in individual lung adenocarcinomas with lymph node metastases

“…To evaluate LOH, we used 24 polymorphic microsatellite markers located at the following sites in the 10 genes reported to play a major role in human carcinogenesis: [13][14][15][16][17][18][19][20][21][22] FHIT (3p) (D3S1300, D3S1312, and D3S1313), APC (5q) (D5S346 and D5S82), p16 (9p) (D9S171 and D9S162), TSC-1 (9q) (D9S149, D9S150 and DBH), Int-2 (11q) (INT-2), Rb (13q) (D13S270, D13S273, and D13S176), TSC-2 (16p) (D16S291 and D16S292), p53 (17p) (TP53 and D17S520), Smad 4 (18q) (D18S46, D18S363, and D18S474), and Band M (22q) (D22S1140, D22S1170, and D22S1161). The use of more than one microsatellite marker ensured a higher yield of information for each genomic locus.…”