title: Validation of methylation markers for diagnosis of oral cavity cancer.
abstract: OBJECTIVE
  Activation of proto-oncogenes and inactivation of tumour suppressor genes are the major genetic alterations involved in carcinogenesis. The increase in methylation at the promoter region of a tumour suppressor gene can lead to gene inactivation, selecting cells with proliferative advantage. Thus, promoter hypermethylation is considered a marker in a variety of malignant tumours, including oral cavity.
  
  
  METHODS
  The methylation pattern of eight genes was evaluated in 40 oral cavity squamous cell carcinomas (OSCCs) and 40 saliva samples from healthy individuals by Q-MSP. Different combinations of genes were also assessed in order to identify gene panels that could better distinguish between OSCC and saliva samples.
  
  
  RESULTS
  CCNA1, DAPK, DCC and TIMP3 methylation were highly specific for being found in the OSCC samples. Moreover, the combination of these genes improved detection when compared with single markers, reaching values of 92.5% for sensitivity and specificity (when using the panel CCNA1, DCC, TIMP3). Moreover, DAPK, DCC and TIMP3 were hypermethylated in nearly 90% of clinically T1 and T2 cases.
  
  
  CONCLUSIONS
  The pursuing of this panel of hypermethylated genes is an important tool for the detection of individuals with OSCC. Moreover, the identification of these markers in early stages of OSCC shows the feasibility of using the panel on saliva as possible biomarkers for early diagnosis. The lack of association between the methylation status of these genes and clinical characteristics shows that they are able to distinguish OSCC cases irrespective of social and clinical factors (gender, age, human papillomavirus (HPV) status, clinical stage, vascular embolisation and perineural invasion).
authors: Department of Molecular Biology, São José do Rio Preto Medical School (FAMERP), São José do Rio Preto, SP, Brazil; Molecular Oncology Research Center, Barretos Cancer Hospital - Pio XII, Barretos, SP, Brazil.
authors: L M R B
authors: LM
authors: Arantes
authors: Molecular Oncology Research Center, Barretos Cancer Hospital - Pio XII, Barretos, SP, Brazil.
authors: A C
authors: AC
authors: de Carvalho
authors: Molecular Oncology Research Center, Barretos Cancer Hospital - Pio XII, Barretos, SP, Brazil.
authors: M E
authors: ME
authors: Melendez
authors: Virology Laboratory, Institute of Tropical Medicine of São Paulo, University of São Paulo, São Paulo, SP, Brazil.
authors: C C
authors: CC
authors: Centrone
authors: Head and Neck Surgery Service, Arnaldo Vieira de Carvalho Cancer Institute (ICAVC), São Paulo, SP, Brazil.
authors: J F
authors: JF
authors: Góis-Filho
authors: Faculty of Public Health, University of São Paulo (FSP), São Paulo, SP, Brazil.
authors: T N
authors: TN
authors: Toporcov
authors: Laboratory of Clinical Pathology, Heliópolis Hospital, São Paulo, SP, Brazil.
authors: D N
authors: DN
authors: Caly
authors: Department of Molecular Biology, São José do Rio Preto Medical School (FAMERP), São José do Rio Preto, SP, Brazil.
authors: E H
authors: EH
authors: Tajara
authors: Department of Molecular Biology, São José do Rio Preto Medical School (FAMERP), São José do Rio Preto, SP, Brazil.
authors: E M
authors: EM
authors: Goloni-Bertollo
authors: Molecular Oncology Research Center, Barretos Cancer Hospital - Pio XII, Barretos, SP, Brazil. Electronic address: alopescarvalho@uol.com.br.
authors: A L
authors: AL
authors: Carvalho
mesh_terms: D000328:Adult; D000368:Aged; D014408:Biomarkers, Tumor / Q000235:genetics*; D001938:Brazil; D002294:Carcinoma, Squamous Cell / Q000235:genetics*; D016022:Case-Control Studies; D056750:Cyclin A1 / Q000235:genetics; D000075389:DCC Receptor; D019175:DNA Methylation; D064550:Death-Associated Protein Kinases / Q000235:genetics; D044127:Epigenesis, Genetic; D005240:Feasibility Studies; D005260:Female; D005820:Genetic Testing / Q000379:methods*; D006258:Head and Neck Neoplasms / Q000235:genetics*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009062:Mouth Neoplasms / Q000235:genetics*; D011237:Predictive Value of Tests; D011401:Promoter Regions, Genetic; D011956:Receptors, Cell Surface / Q000235:genetics; D015203:Reproducibility of Results; D000077195:Squamous Cell Carcinoma of Head and Neck; D019717:Tissue Inhibitor of Metalloproteinase-3 / Q000235:genetics; D025521:Tumor Suppressor Proteins / Q000235:genetics
chemical_list: D014408:Biomarkers, Tumor; C503745:CCNA1 protein, human; D056750:Cyclin A1; D000075389:DCC Receptor; C501909:DCC protein, human; D011956:Receptors, Cell Surface; C088390:TIMP3 protein, human; D019717:Tissue Inhibitor of Metalloproteinase-3; D025521:Tumor Suppressor Proteins; D064550:Death-Associated Protein Kinases
keywords: CCNA1; DAPK; DCC; Methylation markers; OSCC; TIMP3