Molecular evidence supporting the neoplastic nature of odontogenic keratocyst: a laser capture microdissection study of 15 cases.
OBJECTIVE
The bland histology of odontogenic keratocyst (OKC) belies its capacity for aggressive behaviour. Genetic alterations of OKC have not been well studied. We examined the frequency and pattern of allelic imbalance on five different chromosome regions from 15 patients with OKC.


RESULTS
Laser-assisted microdissection was performed on formalin-fixed paraffin-embedded tissue. Polymerase chain reaction analysis of extracted DNA targeted five polymorphic DNA markers (D3S1285, D9S161, D11S1316, D13S290, and TP53) representing chromosome regions 3p14, 9p21, 11q23, 13q12.1 and 17p13, respectively. All 15 cases of OKC were informative at a minimum of three of five loci, with 11 informative on all five loci. Twelve of 15 cases (80%) demonstrated loss of heterozygosity (LOH). Seven cases (47%) showed LOH at more than two DNA loci. The frequency of LOH was 5/11 (45%) at D3S1285, 3/15 (20%) at D9S161, 4/14 (29%) at D11S1316, 8/14 (57%) at D13S290 and 3/15 (20%) at TP53.


CONCLUSIONS
The majority of OKCs harbour chromosomal abnormalities. This finding supports the supposition that OKCs are neoplastic. Furthermore, OKCs harbour allelic loss at some of the same loci identified in squamous cell carcinoma. This may aid in explaining the rare occurrence of squamous cell carcinoma arising in OKC.
Henley
J
J
Department of Pathology and Laboratory Medicine, Indiana University School of Medicine, Indianapolis, USA. jhenley@iupui.edu
Summerlin
D-J
DJ
Tomich
C
C
Zhang
S
S
Cheng
L
L
D000483:Alleles; D002471:Cell Transformation, Neoplastic / Q000235:genetics / Q000473:pathology; D002880:Chromosomes, Human, Pair 11; D002886:Chromosomes, Human, Pair 17; D002893:Chromosomes, Human, Pair 3; D002899:Chromosomes, Human, Pair 9; D005787:Gene Frequency; D005819:Genetic Markers; D006801:Humans; D007834:Lasers; D019656:Loss of Heterozygosity; D008336:Mandibular Diseases / Q000235:genetics* / Q000473:pathology; D008439:Maxillary Diseases / Q000235:genetics* / Q000473:pathology; D042282:Microdissection; D009807:Odontogenic Cysts / Q000235:genetics* / Q000473:pathology
D005819:Genetic Markers