Methylation of P16, P21, P27, RB1 and P53 genes in odontogenic keratocysts.
BACKGROUND
Odontogenic keratocyst (OKC) is a benign neoplasm with an aggressive clinical behavior and a high recurrence rate. Although epigenetic alterations have been reported in different tumors, these events were not investigated in OKC yet. The aim of this study was to investigate the presence of methylation in P16, P21, P27, P53 and RB1 genes in OKC tumors.


METHODS
Methylation-specific polymerase chain reaction (MSP) was used to evaluate the presence of methylation in 10 samples of OKCs, 10 samples of dental follicles and six samples of normal mucosa.


RESULTS
The methylation status of the P16 gene was similar among the three groups. In P21 gene, 30% of OKCs were methylated while no methylation could be detected in the other groups. High frequency of P27 methylation (90%) was observed in dental follicles, however, some OKC lesions (10%) and normal mucosa samples (33%) were also methylated. Concerning the RB1 gene, positive results were detected only in dental follicles (40%). No positive result was observed considering P53 gene.


CONCLUSIONS
Our data show methylation of the promoter of P21 gene in OKCs. In addition, methylation of the P27 and RB1 genes are commonly found in dental follicles. Further studies are necessary to determine the functional relevance of these alterations.
Moreira
Paula Rocha
PR
Laboratory of Molecular Biology, Department of Oral Surgery and Pathology, School of Dentistry, Universidade Federal de Minas Gerais, Minas Gerais, Brazil.
Guimarães
Mariana Moreira
MM
Guimarães
André Luiz Sena
AL
Diniz
Marina Gonçalves
MG
Gomes
Carolina Cavaliéri
CC
Brito
João Artur Ricieri
JA
Gomez
Ricardo Santiago
RS
D000293:Adolescent; D000328:Adult; D002648:Child; D050759:Cyclin-Dependent Kinase Inhibitor p21 / Q000235:genetics; D050760:Cyclin-Dependent Kinase Inhibitor p27 / Q000235:genetics; D019175:DNA Methylation / Q000235:genetics*; D003795:Dental Sac / Q000378:metabolism; D044127:Epigenesis, Genetic / Q000235:genetics; D005260:Female; D016147:Genes, Tumor Suppressor; D019942:Genes, p16; D016158:Genes, p53; D006801:Humans; D008297:Male; D009061:Mouth Mucosa / Q000378:metabolism; D009807:Odontogenic Cysts / Q000235:genetics*; D011401:Promoter Regions, Genetic / Q000235:genetics; D016160:Retinoblastoma Protein / Q000235:genetics; D055815:Young Adult
C493956:CDKN1A protein, human; D050759:Cyclin-Dependent Kinase Inhibitor p21; D016160:Retinoblastoma Protein; D050760:Cyclin-Dependent Kinase Inhibitor p27