title: Prognostic significance of the methylation of Wnt pathway antagonists-CXXC4, DACT2, and the inhibitors of sonic hedgehog signaling-ZIC1, ZIC4, and HHIP in head and neck squamous cell carcinomas.
abstract: OBJECTIVE
  Aberrations in Wnt and Shh signaling pathways are related to the pathogenesis of head and neck carcinomas, and their activation frequently results from epigenetic alterations. This study aimed to assess the frequency of methylation of negative regulators of Wnt signaling: CXXC4, DACT2, HDPR1, and FBXW11 and Shh signaling: HHIP, PTCH1, SUFU, ZIC1, and ZIC4 and correlate it with clinicopathological features in this group of patients.
  
  
  METHODS
  Methylation-specific PCR was used to detect gene promoter methylation, and real-time PCR was used to assess gene expression level.
  
  
  RESULTS
  The analysis of the occurrence of gene promoter methylation in head and neck carcinoma cell lines indicated that CXXC4, DACT2, HHIP, ZIC1, and ZIC4 are methylated in these tumors. These genes were further analyzed in tumor sections from oral and laryngeal cancer patients. Gene methylation rate was higher in laryngeal tumors. The methylation index in tumor samples correlated with the overall survival in a subgroup of oral cancer patients who died of the disease. Moreover, ZIC4 methylation correlated with lymph node involvement in oral cancer patients.
  
  
  CONCLUSIONS
  Our findings corroborate that the activation of Wnt signaling in head and neck squamous cell carcinoma (HNSCC) is related to epigenetic silencing of its negative regulators. Moreover, the results indicate that the same mechanism of activation may operate in the case of Shh signaling.
  
  
  CONCLUSIONS
  The methylation of ZIC4 may be considered a new prognostic marker in oral cavity and oropharyngeal tumors. Further investigations should determine the diagnostic significance of methylation of ZIC4, HHIP, and DACT2 in head and neck carcinomas.
authors.affiliation: Department of Pharmaceutical Biochemistry, Poznan University of Medical Sciences, ul. Święcickiego 4, 60-781, Poznań, Poland. paluszcz@ump.edu.pl.
authors.forename: Jarosław
authors.identifier: http://orcid.org/0000-0002-6187-7549
authors.initials: J
authors.lastname: Paluszczak
authors.affiliation: Department of Pharmaceutical Biochemistry, Poznan University of Medical Sciences, ul. Święcickiego 4, 60-781, Poznań, Poland.
authors.forename: Dorota
authors.initials: D
authors.lastname: Wiśniewska
authors.affiliation: Department of Cancer Genetics, Institute of Human Genetics, Polish Academy of Sciences, Poznań, Poland.
authors.forename: Magdalena
authors.initials: M
authors.lastname: Kostrzewska-Poczekaj
authors.affiliation: Department of Cancer Genetics, Institute of Human Genetics, Polish Academy of Sciences, Poznań, Poland.
authors.forename: Katarzyna
authors.initials: K
authors.lastname: Kiwerska
authors.affiliation: Department of Otorhinolaryngology, Head and Neck Surgery and Department of Medical Biochemistry, Turku University Central Hospital and Turku University, Turku, Finland.
authors.forename: Reidar
authors.initials: R
authors.lastname: Grénman
authors.affiliation: Department of Otolaryngology and Laryngological Oncology, Poznan University of Medical Sciences, Poznań, Poland.
authors.forename: Daniela
authors.initials: D
authors.lastname: Mielcarek-Kuchta
authors.affiliation: Department of Cancer Genetics, Institute of Human Genetics, Polish Academy of Sciences, Poznań, Poland.
authors.forename: Małgorzata
authors.initials: M
authors.lastname: Jarmuż-Szymczak
mesh_terms: D048868:Adaptor Proteins, Signal Transducing; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002294:Carcinoma, Squamous Cell / Q000235:genetics*; D002352:Carrier Proteins / Q000235:genetics; D045744:Cell Line, Tumor; D019175:DNA Methylation; D004268:DNA-Binding Proteins / Q000235:genetics; D044127:Epigenesis, Genetic; D005260:Female; D005387:Finland; D006258:Head and Neck Neoplasms / Q000235:genetics*; D006801:Humans; D008207:Lymphatic Metastasis; D008297:Male; D008562:Membrane Glycoproteins / Q000235:genetics; D008875:Middle Aged; D009363:Neoplasm Proteins / Q000235:genetics; D009419:Nerve Tissue Proteins / Q000235:genetics; D016133:Polymerase Chain Reaction; D011379:Prognosis; D011401:Promoter Regions, Genetic; D015398:Signal Transduction; D000077195:Squamous Cell Carcinoma of Head and Neck; D015996:Survival Rate; D014157:Transcription Factors / Q000235:genetics; D060449:Wnt Signaling Pathway / Q000235:genetics*
chemical_list: D048868:Adaptor Proteins, Signal Transducing; C418221:CXXC4 protein, human; D002352:Carrier Proteins; C478653:DACT2 protein, human; D004268:DNA-Binding Proteins; C117596:HHIP protein, human; D008562:Membrane Glycoproteins; D009363:Neoplasm Proteins; D009419:Nerve Tissue Proteins; D014157:Transcription Factors; C492123:ZIC1 protein, human; C492799:ZIC4 protein, human
keywords: DNA methylation; Head and neck cancer; Shh pathway; Wnt pathway; ZIC4