Identifying Candidate Biomarkers for Pleomorphic Adenoma: A Case-Control Study.

Pleomorphic adenoma (PA) is the most common benign salivary gland tumor. Kallikrein-related peptidases have been identified as biomarkers in many human tumors and may influence tumor behavior. We investigated KLK1-15 messenger ribonucleic acid and proteins in PA specimens to determine a KLK expression profile for this tumor. Fresh frozen PA tissue specimens (n = 26) and matched controls were subjected to quantitative real-time reverse transcription polymerase chain reaction to detect KLK1-15 mRNA. Expression of KLK1, KLK12, KLK13, and KLK8 proteins were then evaluated via immunostaining techniques. Statistical analyses were performed with the level of significance set at P < .05. We observed downregulation of KLK1, KLK12, and KLK13 mRNA expression, and immunostaining studies revealed downregulation of the corresponding proteins. Histologic evidence of capsular perforation was associated with increased KLK1 protein expression. Tumor size was not associated with capsular invasion and/or perforation. This study is the first to detail a KLK expression profile for PA at both the transcriptional level and the protein level. Future work is required to develop clinical applications of these findings.

Ameloblastic fibro-odontoma: a case report.

Ameloblastic fibro-odontoma is a benign epithelial odontogenic tumour with odontogenic mesenchyme exhibiting the histologic characteristics of ameloblastic fibroma and complex odontoma. It is usually associated with developing teeth and occurs predominantly in children and adolescents. In many cases, such lesions are found on radiographic evaluation of patients in whom eruption of teeth is delayed. Ameloblastic fibro-odontoma is generally asymptomatic but may cause swelling and discomfort. This report describes an ameloblastic fibro-odontoma in the posterior mandible of a 26-year-old woman and discusses the histogenesis and clinical features of the lesion.