Mdm2, p53, p21 and pAKT protein pathways in benign neoplasms of the salivary gland

• Published in: Oral oncology Vol. 44; no. 9; pp. 903 - 908
• Main Authors: Marques, Yonara Maria Freire Soares, de Deus Moura de Lima, Marina, de Melo Alves, Sérgio, Augusto Soares, Fernando, de Araújo, Vera Cavalcanti, Pinto, Décio dos Santos, Mantesso, Andrea
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01-09-2008; Elsevier
• Subjects: Biological and medical sciences; Cell Line, Tumor; Cyclin-Dependent Kinase Inhibitor p21 - genetics; Cyclin-Dependent Kinase Inhibitor p21 - metabolism; Genes, p53 - genetics; Hematology, Oncology and Palliative Medicine; Humans; Immunohistochemistry; Mdm2; Medical sciences; Mutation; Myoepithelioma; Otolaryngology; Otorhinolaryngology. Stomatology; p21; p53; pAkt; Pleomorphic adenoma; Proto-Oncogene Proteins c-akt - genetics; Proto-Oncogene Proteins c-akt - metabolism; Proto-Oncogene Proteins c-mdm2 - genetics; Proto-Oncogene Proteins c-mdm2 - metabolism; Salivary Gland Neoplasms - genetics; Salivary Gland Neoplasms - metabolism; Signal Transduction - genetics; Tumor Suppressor Protein p53 - genetics; Tumor Suppressor Protein p53 - metabolism; Tumors; Mdm2; pAkt; Myoepithelioma; Pleomorphic adenoma; p21; p53; Cancerology; Stomatology; p53 Protein; Salivary gland; ENT; Benign neoplasm
• ISSN: 1368-8375; 1879-0593
• DOI: 10.1016/j.oraloncology.2007.11.013

Summary The p53 protein can be altered virtually in all human cancers. In the absence of p53 mutations, p53 inactivation is possible via complex formation with other proteins, such as Mdm2. Previous studies have shown an overexpression of Mdm2 and lack of p 53 expression in pleomorphic adenomas. The pAkt protein is closely related to Mdm2, and has not been previously reported in salivary gland tumors. The aim of this study was to analyze the expression of Mdm2, p53, p21 and pAkt proteins in pleomorphic adenomas and myoepitheliomas by immunohistochemistry, Western blotting and immunofluorescence techniques. Overexpression of Mdm2 and pAkt was present in all the cell lines and tumors studied, whereas the expression of p53 and p21 proteins was considered absent. In conclusion, the signaling pathway in benign salivary gland neoplasm showed an important participation of Mdm2 overexpression protein in tumor formation, progression through inactivation of p53 action, or both, and of pAkt overexpression through increased translocation of Mdm2 protein to cellular nuclei.