title: p16INK4A and p14ARF gene promoter hypermethylation as prognostic biomarker in oral and oropharyngeal squamous cell carcinoma: a review.
abstract: Head and neck squamous cell carcinoma is a heterogeneous group of tumors with each subtype having a distinct histopathological and molecular profile. Most tumors share, to some extent, the same multistep carcinogenic pathways, which include a wide variety of genetic and epigenetic changes. Epigenetic alterations represent all changes in gene expression patterns that do not alter the actual DNA sequence. Recently, it has become clear that silencing of cancer related genes is not exclusively a result of genetic changes such as mutations or deletions, but it can also be regulated on epigenetic level, mostly by means of gene promoter hypermethylation. Results from recent studies have demonstrated that DNA methylation patterns contain tumor-type-specific signatures, which could serve as biomarkers for clinical outcome in the near future. The topic of this review discusses gene promoter hypermethylation in oral and oropharyngeal squamous cell carcinoma (OSCC). The main objective is to analyse the available data on gene promoter hypermethylation of the cell cycle regulatory proteins p16(INK4A) and p14(ARF) and to investigate their clinical significance as novel biomarkers in OSCC. Hypermethylation of both genes seems to possess predictive properties for several clinicopathological outcomes. We conclude that the methylation status of p16(INK4A) is definitely a promising candidate biomarker for predicting clinical outcome of OSCC, especially for recurrence-free survival.
authors.affiliation: Department of Pathology, University Medical Centre Utrecht, P.O. Box 85500, 3508 GA Utrecht, The Netherlands.
authors.forename: A
authors.initials: A
authors.lastname: Al-Kaabi
authors.affiliation: Department of Radiation Oncology, University Medical Centre Utrecht, P.O. Box 85500, 3508 GA Utrecht, The Netherlands.
authors.forename: L W
authors.initials: LW
authors.lastname: van Bockel
authors.affiliation: Department of Otorhinolaryngology, University Medical Centre Utrecht, P.O. Box 85500, 3508 GA Utrecht, The Netherlands.
authors.forename: A J
authors.initials: AJ
authors.lastname: Pothen
authors.affiliation: Department of Pathology, University Medical Centre Utrecht, P.O. Box 85500, 3508 GA Utrecht, The Netherlands.
authors.forename: S M
authors.initials: SM
authors.lastname: Willems
mesh_terms: D000818:Animals; D014408:Biomarkers, Tumor / Q000235:genetics*; D002294:Carcinoma, Squamous Cell / Q000235:genetics*; D019941:Cyclin-Dependent Kinase Inhibitor p16 / Q000235:genetics*; D019175:DNA Methylation; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D009062:Mouth Neoplasms / Q000235:genetics*; D011379:Prognosis; D011401:Promoter Regions, Genetic; D025803:Tumor Suppressor Protein p14ARF / Q000235:genetics*
chemical_list: D014408:Biomarkers, Tumor; D019941:Cyclin-Dependent Kinase Inhibitor p16; D025803:Tumor Suppressor Protein p14ARF