title: Expression of ets-1 is not affected by N-ras or H-ras during oral oncogenesis.
abstract: OBJECTIVE
  To determine whether ras-activated cascades lead to activation of ets-1 expression in sequential histological stages of oral oncogenesis in an experimental animal model.
  
  
  METHODS
  Thirty-seven Syrian golden hamsters were divided into three experimental groups (A, B, C) and one control group. The hamsters' buccal pouches in experimental groups were treated with 0.5% 9, 10-dimethyl-1, 2-benzanthracene (DMBA) for 14 weeks and were excised at 10, 14, 19 weeks, respectively. The biopsies were classified pathologically (normal mucosa, hyperkeratosis, hyperplasia, dysplasia, early invasion, well and moderately differentiated carcinoma) and studied immunohistochemically. The two-tailed Student's t test was performed for each animal group and for each histological category.
  
  
  RESULTS
  The ets-1 expression increased in early stages of oral tumor formation and invasion. The expression of N-ras gradually decreased during oral oncogenesis, as previously observed with H-ras.
  
  
  CONCLUSIONS
  Neither N-ras nor H-ras affects ets-1 expression in contrast to other types of cancer in which N-ras and ets-1 are implicated in the same signalling pathway. Therefore, the existing pathway implicating these proteins might be somehow altered in oral cancer. It seems that ets-1 is a good prognostic marker for invasiveness and progression of oral cancer.
authors.affiliation: Department of Oral and Maxillofacial Surgery, University of Athens Medical School, Vas. Sofias 93 and Dim. Soutsou 1, Athens 11521, Greece.
authors.forename: Eleftherios
authors.initials: E
authors.lastname: Vairaktaris
authors.forename: Georgios
authors.initials: G
authors.lastname: Papageorgiou
authors.forename: Spyridoula
authors.initials: S
authors.lastname: Derka
authors.forename: Panagiota
authors.initials: P
authors.lastname: Moulavassili
authors.forename: Emeka
authors.initials: E
authors.lastname: Nkenke
authors.forename: Peter
authors.initials: P
authors.lastname: Kessler
authors.forename: Stavros
authors.initials: S
authors.lastname: Vassiliou
authors.forename: Veronica
authors.initials: V
authors.lastname: Papakosta
authors.forename: Sofia
authors.initials: S
authors.lastname: Spyridonidou
authors.forename: Antonis
authors.initials: A
authors.lastname: Vylliotis
authors.forename: Andreas C
authors.initials: AC
authors.lastname: Lazaris
authors.forename: Sofia
authors.initials: S
authors.lastname: Anagnostopoulou
authors.forename: Constantinos
authors.initials: C
authors.lastname: Mourouzis
authors.forename: Christos
authors.initials: C
authors.lastname: Yapijakis
authors.forename: Efstratios
authors.initials: E
authors.lastname: Patsouris
mesh_terms: D015127:9,10-Dimethyl-1,2-benzanthracene; D000818:Animals; D006224:Cricetinae; D015972:Gene Expression Regulation, Neoplastic / Q000235:genetics*; D011905:Genes, ras / Q000235:genetics*; D006965:Hyperplasia / Q000139:chemically induced / Q000235:genetics; D007150:Immunohistochemistry / Q000706:statistics & numerical data; D007972:Leukoplakia, Oral / Q000139:chemically induced / Q000235:genetics; D008297:Male; D009062:Mouth Neoplasms / Q000139:chemically induced / Q000235:genetics*; D011230:Precancerous Conditions / Q000139:chemically induced / Q000235:genetics; D050784:Proto-Oncogene Protein c-ets-1 / Q000378:metabolism*; D011897:Random Allocation
chemical_list: D050784:Proto-Oncogene Protein c-ets-1; D015127:9,10-Dimethyl-1,2-benzanthracene