Presence of ghost cells and the Wnt signaling pathway in odontomas.
BACKGROUND
Although it has been reported that ghost cells are present in odontomas, the generation mechanism of these cells is unclear. To evaluate the presence of ghost cells and involvement of the Wnt signaling pathway, we examined the expression of hard keratins, beta-catenin and Lef-1 in odontomas.


METHODS
Sixty-nine cases of odontoma were examined immunohistochemically with the use of antibodies against human hair proteins, beta-catenin and Lef-1.


RESULTS
Expression of hard keratins was found only in the cytoplasm of ghost cells in 46 (66.7%) of the 69 odontomas. Compound odontomas (78.8%) showed a higher incidence of ghost cells than complex odontomas (29.4%). Histopathologically, ghost cells were found within odontogenic epithelium adjacent to immature enamel and in the centre of Liesegang-ring-like calcified materials. Expression of beta-catenin and Lef-1 was observed in the cytoplasm and nucleus of odontogenic epithelial cells adjacent to the ghost cells in immature odontomas.


CONCLUSIONS
These findings suggest that odontoma is a hard keratin-expressing tumor-like lesion, and that the Wnt signaling pathway may be involved in the formation of ghost cells in odontomas.
Tanaka
Akio
A
Division of Pathology, Department of Diagnostic and Therapeutic Sciences, Meikai University School of Dentistry, Saitama, Japan. akio.t@dent.meikai.ac.jp
Okamoto
Motoyoshi
M
Yoshizawa
Dai
D
Ito
Shigeru
S
Alva
Patricia González
PG
Ide
Fumio
F
Kusama
Kaoru
K
D000293:Adolescent; D000328:Adult; D000368:Aged; D002467:Cell Nucleus / Q000648:ultrastructure; D002648:Child; D002675:Child, Preschool; D003593:Cytoplasm / Q000648:ultrastructure; D003743:Dental Enamel / Q000473:pathology; D004848:Epithelium / Q000473:pathology; D005260:Female; D006801:Humans; D007633:Keratins / Q000032:analysis; D051821:Lymphoid Enhancer-Binding Factor 1 / Q000032:analysis; D008297:Male; D008339:Mandibular Neoplasms / Q000473:pathology; D008441:Maxillary Neoplasms / Q000473:pathology; D008875:Middle Aged; D009810:Odontoma / Q000473:pathology*; D015398:Signal Transduction / Q000502:physiology; D051153:Wnt Proteins / Q000032:analysis*; D051176:beta Catenin / Q000032:analysis
C495270:CTNNB1 protein, human; D051821:Lymphoid Enhancer-Binding Factor 1; D051153:Wnt Proteins; D051176:beta Catenin; D007633:Keratins