• ameloblastoma;
  • keratocystic odontogenic tumor;
  • LINE-1;
  • methylation level;

Oral Diseases (2010) 16, 286–291

Objective:  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 = 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.