Pleomorphic adenoma and adenoid cystic carcinoma of salivary glands: E-cadherin immunoexpression and analysis of the CDH1 -160C/A polymorphism Roberta Barroso Cavalcante, DDS, PhD a , Cassiano Francisco Weege Nonaka, DDS, PhD b , Silvia Helena Barem Rabenhorst, PhD c , Márcia Cristina da Costa Miguel, DDS, PhD d , Leão Pereira Pinto, DDS, PhD d , Lélia Batista de Souza, DDS, PhD d, * a Department of Oral Pathology, University of Fortaleza, Fortaleza, CE, Brazil b Department of Dentistry, State University of Paraíba, Campina Grande, PB, Brazil c Molecular Genetics Laboratory, Department of Pathology and Forensic Medicine, Federal University of Ceará, Fortaleza, CE, Brazil d Department of Oral Pathology, Federal University of Rio Grande do Norte, Natal, RN, Brazil A R T I C L E I N F O Article history: Received 1 August 2015 Received in revised form 9 September 2016 Accepted 14 September 2016 Keywords: Pleomorphic adenoma Adenoid cystic carcinoma E-Cadherin CDH1 gene Polymorphism A B S T R A C T Objective: Despite their similar cellular origin, pleomorphic adenomas (PA) and adenoid cystic carcinomas (ACC) present distinct behaviors. This study aimed to analyze the immunoexpression of E- cadherin in PA and ACC of salivary glands, and to investigate differences in its expression in relation to E- cadherin gene (CDH1) -160C/A polymorphism. Design: Twenty-four PA (15 cell-rich and 9 cell-poor tumors) and 24 ACC (10 tubular, 8 cribriform and 6 solid tumors) were selected for the analysis of pattern of distribution, and cellular localization of E- cadherin. In addition, E-cadherin expression was evaluated using the H-score scoring system. The CDH1 -160C/A polymorphism was investigated by PCR-RFLP. Results: No significant differences in pattern of distribution (p = 0.181) and cellular localization (p = 0.192) of E-cadherin were observed between PA and ACC. Comparison of PA and ACC cases revealed a higher median H-score in the latter (p = 0.036). Cell-rich PA presented a higher H-score than cell-poor tumors (p = 0.013), whereas no significant differences in E-cadherin expression were observed between ACC subtypes (p = 0.254). The heterozygous genotype of the CDH1 -160C/A polymorphism was detected in only one PA and one ACC. H-scores for tumors carrying the polymorphism were below the lower quartile of their respective groups. Conclusions: The results suggest that E-cadherin expression in PA and ACC is mainly related to cellular composition (epithelial cells versus myoepithelial cells) and degree of differentiation of myoepithelial cells in these tumors. The CDH1 -160C/A polymorphism does not seem to significantly influence the expression of E-cadherin in PA and ACC of salivary glands. ã 2016 Elsevier Ltd. All rights reserved. 1. Introduction Salivary gland tumors are a fairly heterogeneous group of neoplasms that are characterized by marked variations in their clinical and histological features. Pleomorphic adenomas (PA) are the most common benign salivary gland tumors, whereas adenoid cystic carcinomas (ACC) are the second most frequent malignant salivary gland neoplasms (Jones, Craig, Speight, & Franklin, 2008). Despite their similar origin and cell components, these tumors present distinct behaviors (Lourenço & Lima, 2007). ACC is a relatively slow-growing malignancy, but is highly invasive (West- ernoff, Jordan, Regezi, Ramos, & Schmidt, 2005). Frequent local recurrences and late distant metastases account for the poor prognosis of ACC (van Weert, van der Waal, Witte, Leemans, & Bloemena, 2015). Conversely, PA is a benign neoplasm that grows and expands circumferentially, causing compression of surround- ing tissues, and therefore has an excellent prognosis (Westernoff et al., 2005). Cadherins comprise a large family of transmembrane glyco- proteins that mediate Ca 2+ -dependent cell-cell adhesion and play pivotal roles in cell adhesion, tissue architecture, and development * Correspondance to: Universidade Federal do Rio Grande do Norte, Departa- mento de Odontologia, Av. Senador Salgado Filho, 1787, Lagoa Nova, Natal, Rio Grande do Norte, CEP 59056-000, Brazil. E-mail address: leliabsouza@gmail.com (L.B. de Souza). http://dx.doi.org/10.1016/j.archoralbio.2016.09.005 0003-9969/ã 2016 Elsevier Ltd. All rights reserved. Archives of Oral Biology 73 (2017) 48–54 Contents lists available at ScienceDirect Archives of Oral Biology journal homepage: www.elsev ier.com/locate /aob