Immunohistochemical detection of BH3-only proteins in ameloblastic tumors.
OBJECTIVE
To evaluate expression of BH3-only proteins in odontogenic tumors, expression of Bid, Bim, Bad, Noxa, and Puma was analyzed in ameloblastic tumors as well as in tooth germs.


METHODS
Nine tooth germs, 37 ameloblastomas, and five malignant ameloblastic tumors were examined immunohistochemically with antibodies against Bid, Bim, Bad, Noxa, and Puma.


RESULTS
Immunohistochemical reactivity for Bid, Bim, Bad, Noxa, and Puma was detected in the cytoplasm of cellular components in normal and neoplastic odontogenic tissues. Expression of these BH3-only proteins was evident in odontogenic epithelial cells near the basement membrane in tooth germs and ameloblastic tumors. Acanthomatous ameloblastomas showed no reactivity for Bid, Bim, Bad, Noxa, or Puma in keratinizing cells, whereas granular cells in granular cell ameloblastomas reacted with these BH3-only proteins. Basal and desmoplastic ameloblastomas and ameloblastic carcinomas showed immunoreactivity for the BH3-only proteins in most neoplastic cells.


CONCLUSIONS
Expression of Bid, Bim, Bad, Noxa, and Puma in tooth germs and ameloblastic tumors suggests that the BH3-only proteins have a role in apoptotic cell death of normal and neoplastic odontogenic epithelium. Distinctive expression patterns of these BH3-only proteins in ameloblastoma variants suggest that the BH3-only proteins might be involved in tumor cell differentiation of ameloblastomas.
Kumamoto
H
H
Division of Oral Pathology, Department of Oral Medicine and Surgery, Tohoku University Graduate School of Dentistry, Sendai, Japan. kumamoto@mail.tains.tohoku.ac.jp
Ooya
K
K
D000564:Ameloblastoma / Q000145:classification / Q000473:pathology*; D051017:Apoptosis Regulatory Proteins / Q000032:analysis*; D051023:BH3 Interacting Domain Death Agonist Protein / Q000032:analysis; D001485:Basement Membrane / Q000473:pathology; D000072224:Bcl-2-Like Protein 11; D002454:Cell Differentiation; D003743:Dental Enamel / Q000473:pathology; D003795:Dental Sac / Q000473:pathology; D042783:Endothelial Cells / Q000473:pathology; D004847:Epithelial Cells / Q000473:pathology; D005347:Fibroblasts / Q000473:pathology; D006801:Humans; D007150:Immunohistochemistry; D007633:Keratins; D008565:Membrane Proteins / Q000032:analysis; D008648:Mesoderm / Q000473:pathology; D011518:Proto-Oncogene Proteins / Q000032:analysis; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000032:analysis*; D014083:Tooth Germ / Q000473:pathology; D051025:bcl-Associated Death Protein / Q000032:analysis
D051017:Apoptosis Regulatory Proteins; C494819:BAD protein, human; C438378:BBC3 protein, human; C000606775:BCL2L11 protein, human; D051023:BH3 Interacting Domain Death Agonist Protein; C494814:BID protein, human; D000072224:Bcl-2-Like Protein 11; D008565:Membrane Proteins; C498702:PMAIP1 protein, human; D011518:Proto-Oncogene Proteins; D019253:Proto-Oncogene Proteins c-bcl-2; D051025:bcl-Associated Death Protein; D007633:Keratins