Calcifying epithelial odontogenic (Pindborg) tumor-associated amyloid consists of a novel human protein.

Abstract

Calcifying epithelial odontogenic tumors (CEOTs), also known as Pindborg tumors, are characterized by the presence of squamous-cell proliferation, calcification, and, notably, amyloid deposits. On the basis of immunohistochemical analyses, the amyloidogenic component had heretofore been deemed to consist of cytokeratin-related or other molecules; however, its chemical composition had never been elucidated. We have used our microanalytic techniques to characterize the protein nature of CEOT-associated amyloid isolated from specimens obtained from 3 patients. As evidenced by the results of amino-acid sequencing and mass spectrometry, the fibrils were found to be composed of a polypeptide of approximately 46 mer. This component was identical in sequence to the N-terminal portion of a hypothetical 153-residue protein encoded by the FLJ20513 gene cloned from the human KATO III cell line. That the amyloid protein was derived from this larger molecule was demonstrated by reverse transcription-polymerase chain reaction amplification of tumor-cell RNA where a full-length FLJ20513 transcript was found. Furthermore, immunohistochemical analyses revealed that the amyloid within the CEOTs immunostained with antibodies prepared against a synthetic FLJ20513-related dodecapeptide. Our studies provide unequivocal evidence that CEOT-associated amyloid consists of a unique and previously undescribed protein that we provisionally designate APin.

• Authors: Alan Solomon, Charles L Murphy, Kristal Weaver, Deborah T Weiss, Rudi Hrncic, Manfred Eulitz, Robert L Donnell, Knut Sletten, Gunilla Westermark, Per Westermark
• Journal: The Journal of laboratory and clinical medicine (J Lab Clin Med) Vol. 142 Issue 5 Pg. 348-55 (Nov 2003) ISSN: 0022-2143 [Print] United States
• PMID: 14647039 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't, Research Support, U.S. Gov't, P.H.S.)

Chemical References

• Amyloid
• Antibodies
• Neoplasm Proteins
• ODAM protein, human

Topics

• Adolescent
• Amino Acid Sequence
• Amyloid (analysis, genetics, immunology)
• Amyloidosis (metabolism, pathology)
• Antibodies
• Cloning, Molecular
• Female
• Humans
• Immunohistochemistry
• Jaw Neoplasms (chemistry, pathology)
• Middle Aged
• Molecular Sequence Data
• Neoplasm Proteins (analysis, genetics, immunology)
• Odontogenic Cyst, Calcifying (chemistry, pathology)