title: EGFR and c-Jun exhibit the same pattern of expression and increase gradually during the progress of oral oncogenesis.
abstract: BACKGROUND
  Epidermal growth factor receptor (EGFR) and c-Jun oncogenes are implicated in the same pathway of signal transduction affecting cell differentiation. In order to investigate their possible correlation with sequential histological stages of OSCC formation, we established an experimental model of induced oral carcinogenesis in Syrian golden hamsters.
  
  
  METHODS
  Thirty-seven animals were divided into one control group (n=7) and three experimental groups (n = 10 each), which were treated with a carcinogen and sacrificed at 10, 14 and 19 weeks after treatment. Tumour sections were studied using monoclonal antibodies against EGFR and c-Jun proteins.
  
  
  RESULTS
  The same pattern of expression was observed for both oncogenes, with a significant gradual increase of positively stained cells throughout oral carcinogenesis.
  
  
  CONCLUSIONS
  Since EGFR and c-Jun are implicated in the same molecular pathway of signal transduction, it may be assumed that an increase in EGFR levels leads to increased activation of phospholipase Cy signal transduction cascade, which in turn activates c-Jun protein. Therefore, c-Jun expression in oral cancer seems to be increased through the EGFR-PLCy-Raf-MEK-ERK pathway and not the H-ras-Raf-MEK-ERK/JNK pathway.
authors.affiliation: Department of Oral and Maxillofacial Surgery, University of Athens Medical School, Athens 11521, Greece. lvairakt@med.uoa.gr
authors.forename: Eleftherios
authors.initials: E
authors.lastname: Vairaktaris
authors.forename: Sofia
authors.initials: S
authors.lastname: Loukeri
authors.forename: Stavros
authors.initials: S
authors.lastname: Vassiliou
authors.forename: Emeka
authors.initials: E
authors.lastname: Nkenke
authors.forename: Sofia
authors.initials: S
authors.lastname: Spyridonidou
authors.forename: Antonis
authors.initials: A
authors.lastname: Vylliotis
authors.forename: Veronica
authors.initials: V
authors.lastname: Papakosta
authors.forename: Andreas
authors.initials: A
authors.lastname: Lazaris
authors.forename: Giorgos
authors.initials: G
authors.lastname: Agrogiannis
authors.forename: Christos
authors.initials: C
authors.lastname: Yapijakis
authors.forename: Despina
authors.initials: D
authors.lastname: Perrea
authors.forename: Efstratios
authors.initials: E
authors.lastname: Patsouris
mesh_terms: D000818:Animals; D001706:Biopsy; D002471:Cell Transformation, Neoplastic / Q000378:metabolism* / Q000473:pathology*; D006224:Cricetinae; D018450:Disease Progression; D066246:ErbB Receptors / Q000378:metabolism*; D048031:JNK Mitogen-Activated Protein Kinases / Q000378:metabolism*; D008297:Male; D009062:Mouth Neoplasms / Q000378:metabolism* / Q000473:pathology*; D011230:Precancerous Conditions / Q000378:metabolism / Q000473:pathology
chemical_list: D066246:ErbB Receptors; D048031:JNK Mitogen-Activated Protein Kinases