Journal of Clinical Medicine Review Saliva Gene Promoter Hypermethylation as a Biomarker in Oral Cancer Óscar Rapado-González 1,2,3 , José Luis López-Cedrún 4 , Rafael López-López 2,3 , Ana María Rodríguez-Ces 1 and María Mercedes Suárez-Cunqueiro 1,2,3,* 1 Department of Surgery and Medical-Surgical Specialties, Medicine and Dentistry School, Universidade de Santiago de Compostela, 15782 Santiago de Compostela, Spain;
[email protected] (Ó.R.-G.);
[email protected] (A.M.R.-C.) 2 Translational Medical Oncology Group (Oncomet), Health Research Institute of Santiago (IDIS), Complexo Hospitalario Universitario de Santiago de Compostela (SERGAS), 15706 Santiago de Compostela, Spain;
[email protected] 3 Centro de Investigación Biomédica en Red en Cáncer (CIBERONC), Instituto de Salud Carlos III, 28029 Madrid, Spain 4 Department of Oral and Maxillofacial Surgery, Complexo Hospitalario Universitario de A Coruña (SERGAS), 15006 A Coruña, Spain;
[email protected] * Correspondence:
[email protected]; Tel.: +34-881-812-437 Abstract: Oral carcinogenesis is a multistep process characterized by a summation of multiple genetic and epigenetic alterations in key regulatory genes. The silencing of genes by aberrant promoter hypermethylation is thought to be an important epigenetic event in cancer development and progression which has great potential as a biomarker for early diagnosis, tumor molecular subtyping, prognosis, monitoring, and therapy. Aberrant DNA methylation has been detected in different liquid biopsies, which may represent a potential alternative to solid biopsies. The detection Citation: Rapado-González, Ó.; López-Cedrún, J.L.; López-López, R.; of methylated genes in saliva may have clinical application for noninvasive oral cancer screening and Rodríguez-Ces, A.M.; early diagnosis.