LINE‐1 methylation difference between ameloblastoma and keratocystic odontogenic tumor

Oral Diseases (2010) 16, 286–291Objective:  Global hypomethylation is a common epigenetic event in cancer. Keratocystic odontogenic tumor (KCOT) and ameloblastoma are different tumors but posses the same tissue in origin. Here, we investigated long interspersed nuclear element‐1 (LINE‐1 or L1) methylation status between ameloblastoma and KCOT.Materials and methods:  We studied the methylation levels of the long interspersed nucleotide element‐1 (LINE‐1) in ameloblastoma and KCOT. After collecting ameloblastoma cells and epithelium lining cells of KCOT by laser capture microdissection from paraffin embedded tissue, combined bisulfite restriction analysis of LINE‐1 (COBRALINE‐1) was performed to measure LINE‐1 methylation levels.Results:  The LINE‐1 methylation level in KCOT (53.16 ± 12.03%) was higher than that in ameloblastoma (36.90 ± 16.52%), with a statistical significance of P = 0.001. The ranges of LINE‐1 methylation of both lesions were not associated with either age or sex.Conclusion:  We found LINE‐1 hypomethylation levels between ameloblastoma and KCOT are different. Therefore, global methylations between these tumors are processed differently.