Hypomethylation of tumor suppressor genes in odontogenic myxoma.
Odontogenic myxoma (OM) is an ectomesenchymal benign odontogenic tumor characterized by spindle or stellate-shaped cells embedded in an abundant myxoid or mucoid extracellular matrix. DNA methylation is characterized by the addition of methyl groups in cytosines within CpG islands in the promoter gene. DNA methylation can decrease the expression of tumor suppressor genes and contribute to the development of neoplastic lesions. The aim of study was to evaluate the methylation pattern of the tumor suppressor genes P16 (CDKN2A), P21 (CDKN1A), P27 (CDKN1B), P53 (TP53) and RB1 in OM and dental pulp. Methylation was evaluated using methylation-specific polymerase chain reaction (PCR). The transcription was studied in some cases by using reverse transcription quantitative PCR. A higher frequency of unmethylated P27, P53, and RB1 samples was observed in the OM when compared with the dental pulp. OM expressed mRNA of all the genes evaluated. Considering all the samples together, the expression of Rb was higher in the unmethylated samples compared with the partially methylated samples. This investigation revealed hypomethylation of the genes P27, P53, and RB1 in OM. In addition, methylation of tumor suppressor genes was found to be an usual event in normal dental pulp.
Laboratory of Cell-Cell Interactions, Department of Morphology, Institute of Biological Sciences, UFMG - Federal University of Minas Gerais, Belo Horizonte, MG, Brazil. paularocha@ufmg.br
Paula Rocha
PR
Moreira
Fabiano Pereira
FP
Cardoso
João Artur Ricieri
JA
Brito
Aline Carvalho
AC
Batista
Carolina Cavaliéri
CC
Gomes
Ricardo Santiago
RS
Gomez
D000293:Adolescent; D000328:Adult; D018899:CpG Islands / Q000235:genetics; D050759:Cyclin-Dependent Kinase Inhibitor p21 / Q000235:genetics; D050760:Cyclin-Dependent Kinase Inhibitor p27 / Q000235:genetics; D003596:Cytosine; D019175:DNA Methylation / Q000235:genetics*; D003782:Dental Pulp / Q000378:metabolism; D005260:Female; D015972:Gene Expression Regulation, Neoplastic / Q000235:genetics; D016147:Genes, Tumor Suppressor / Q000502:physiology*; D019942:Genes, p16 / Q000502:physiology; D016158:Genes, p53 / Q000235:genetics; D006801:Humans; D008297:Male; D009808:Odontogenic Tumors / Q000235:genetics*; D016133:Polymerase Chain Reaction; D011401:Promoter Regions, Genetic / Q000235:genetics; D012333:RNA, Messenger / Q000235:genetics; D016160:Retinoblastoma Protein / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014158:Transcription, Genetic / Q000235:genetics; D055815:Young Adult
C493956:CDKN1A protein, human; C436291:CDKN1B protein, human; D050759:Cyclin-Dependent Kinase Inhibitor p21; D012333:RNA, Messenger; D016160:Retinoblastoma Protein; D050760:Cyclin-Dependent Kinase Inhibitor p27; D003596:Cytosine