EGF in Saliva and Tumor Samples of Oral Squamous Cell Carcinoma Vanessa Fa´tima Bernardes, PhD,* Frederico Omar Gleber-Netto, DDS,* Sı´lvia Ferreira Sousa, DDS,* Tarcı´lia Aparecida Silva, PhD,* Mauro Henrique Nogueira Guimara˜es Abreu, PhD,w and Maria Ca´ssia Ferreira Aguiar, PhD* Abstract: The objective of this research was to investigate the salivary levels of epidermal growth factor (EGF) in patients with oral squamous cell carcinoma (OSCC) in comparison with clinically healthy individuals and to verify the immunoexpres- sion of EGF in tumor samples. In addition, the relationship between salivary levels and tumoral EGF expression with clinicopathologic features was investigated. We carried out an investigation on EGF expression in lesion samples and in saliva of OSCC patients through immunohistochemistry and enzyme- linked immunosorbent assay, respectively. EGF salivary levels of OSCC patients were also compared with levels in saliva of healthy controls. EGF levels were significantly lower in OSCC patients in comparison with the control group. Smoking, tumor location, and alcohol consumption affected salivary levels of EGF. Strong immunoexpression of EGF was associated with a more aggressive histologic pattern of the lesion. There was no significant association among salivary levels and immunohisto- chemical expression of EGF. Although EGF expression is fre- quently observed in tumors, salivary levels of EGF are reduced in patients with OSCC samples. Tobacco and alcohol may decrease EGF in saliva, which may contribute to oral carcino- genesis. Indeed, further investigations are needed to elucidate the EGF pathways. Key Words: oral carcinoma, epidermal growth factor, saliva, immunohistochemistry (Appl Immunohistochem Mol Morphol 2011;19:528–533) S quamous cell carcinoma (SCC) is the most frequent cancer in the oral and maxillofacial region. 1 Despite progress recorded in the diagnosis and treatment of oral SCC (OSCC), little is known about the importance of the oral environment and saliva in the development of this neoplasm. 2 Epidermal growth factor (EGF) is a 53-aminoacids polypeptide, originally isolated from mouse salivary glands. In humans, synthesis of EGF is done mainly in salivary glands, making saliva a potential source of EGF in the oral milieu, whereas kidneys are responsible for systemic EGF production. 2 EGF biological activities depend upon its binding to the EGF receptor, which is involved in activating pathways that promote cellular proliferation, survival, migration, and differentiation in the majority of epithelial tissues, fibroblasts, and en- dothelial cells. 2,3 Evidence indicates that salivary EGF is a cytoprotective factor against injuries and contributes to the maintenance of the integrity of the gastrointestinal mucosa, including the oral cavity mucous membrane, protecting the oral mucosa from various injurious sub- stances. 2,4,5 However, few studies have evaluated EGF present in saliva or have investigated factors that could interfere with its expression and the association between salivary and tumoral EGF levels. 2,6 On the basis of these considerations, this study proposed to verify the level of this protein in saliva and its immunoexpression in the neoplastic tissue of patients with OSCC. Moreover, the clinicopathologic features were compared with salivary levels and tumoral EGF expression. MATERIALS AND METHODS The protocol of this study was approved by the Research Ethics Committee from Universidade Federal de Minas Gerais (87/07), and a signed informed consent was obtained from all participants. Patients Patients with a histopathologic diagnosis of OSCC were enrolled in this research. Clinical data, such as age, sex, symptoms, location, and extension of the tumor, nodal involvement, and tobacco and alcohol habits were obtained from medical records. The saliva was collected at the moment of diagnosis. The control group included healthy individuals without oral lesions and who had been matched by age, sex, and tobacco usage with OSCC group. 7 Copyright r 2011 by Lippincott Williams & Wilkins Received for publication November 3, 2010; accepted February 4, 2011. From the *Department of Oral Surgery and Pathology, School of Dentistry, Universidade Federal de Minas Gerais, Belo Horizonte, MG; and wDepartment of Community and Preventive Dentistry, School of Dentistry, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil. Funding was provided by the Research Foundation of the State of Minas Gerais (FAPEMIG-CDS APQ-1580) and the National Council for Scientific and Technological Development (CNPq). The authors declare no conflict of interest. Reprints: Maria Ca´ssia Ferreira Aguiar, Faculdade de Odontologia da UFMG, Laborato´rio de Patologia Experimental 1-Sala 3201, PampulhaFBelo Horizonte, MG (e-mail: cassiafa@ufmg.br). RESEARCH ARTICLE 528 | www.appliedimmunohist.com Appl Immunohistochem Mol Morphol  Volume 19, Number 6, December 2011