title: Expression of survivin and X chromosome-linked inhibitor of apoptosis protein in ameloblastomas.
abstract: To clarify the role of apoptosis in oncogenesis and cytodifferentiation of odontogenic epithelium, expression of survivin and X chromosome-linked inhibitor of apoptosis protein (XIAP), inhibitor of apoptosis protein (IAP) family proteins, was examined in tooth germs and in benign and malignant ameloblastomas by means of immunohistochemistry and reverse-transcription polymerase chain reaction. Immunoreactivity for survivin and XIAP was detected in developing and neoplastic odontogenic epithelium. In tooth germs, survivin expression was evident in inner enamel epithelium. Follicular, plexiform and metastasizing ameloblastomas showed survivin reactivity chiefly in neoplastic cells neighboring the basement membrane, and most neoplastic cells in basal cell and desmoplastic ameloblastomas and ameloblastic carcinomas were positive for survivin. Survivin mRNA levels were slightly higher in ameloblastomas than in tooth germs, suggesting that elevation of survivin expression might be involved in oncogenesis of odontogenic epithelium. Immunoreactivity for XIAP was detected in most odontogenic epithelial cells in tooth germs and in benign and malignant ameloblastomas, and XIAP mRNA levels were significantly higher in follicular ameloblastomas than in plexiform ameloblastomas. The expression of survivin and XIAP in odontogenic tissues suggests that these IAP family proteins contribute to the biological properties of ameloblastomas, such as cell survival, proliferation, differentiation and tissue structuring, as well as to cellular regulation during tooth development.
authors.affiliation: Division of Oral Pathology, Department of Oral Medicine and Surgery, Tohoku University Graduate School of Dentistry, 4-1 Seiryo-machi, Aoba-ku, 980-8575, Sendai, Japan. kumamoto@mail.tains.tohoku.ac.jp
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Kumamoto
authors.forename: Kiyoshi
authors.initials: K
authors.lastname: Ooya
mesh_terms: D000564:Ameloblastoma / Q000378:metabolism*; D017209:Apoptosis / Q000502:physiology*; D041321:Chromosomes, Human, X; D008040:Genetic Linkage; D006801:Humans; D007150:Immunohistochemistry; D051034:Inhibitor of Apoptosis Proteins; D007573:Jaw Neoplasms / Q000378:metabolism*; D008869:Microtubule-Associated Proteins / Q000096:biosynthesis*; D009363:Neoplasm Proteins; D014176:Protein Biosynthesis; D011506:Proteins; D012333:RNA, Messenger / Q000032:analysis; D020133:Reverse Transcriptase Polymerase Chain Reaction; D000077022:Survivin; D014083:Tooth Germ / Q000378:metabolism
chemical_list: C107489:BIRC5 protein, human; D051034:Inhibitor of Apoptosis Proteins; D008869:Microtubule-Associated Proteins; D009363:Neoplasm Proteins; D011506:Proteins; D012333:RNA, Messenger; D000077022:Survivin