title: Immunohistochemical evaluation of TGF-beta and extracellular matrix proteins expression in rat squamous cell carcinomas.
abstract: OBJECTIVE
  The aim of this study was to establish a possible association between the degree of differentiation of squamous cell carcinomas (SCC) derived from rat oral tissues treated in vivo with carcinogen 4NQO, and the expression of TGF-beta on epithelial cells and the distribution of extracellular matrix proteins (laminin-collagen type IV).
  
  
  METHODS
  A parent tumor showing a spectrum of differentiation was used to establish clonal subpopulations that formed differentiated SCC and undifferentiated (spindle cell phenotype) tumours following transplantation to athymic mice.
  
  
  RESULTS
  Immunohistological findings revealed the absence of TGF-beta staining on epithelial cells and extracellular matrix proteins in spindle cell tumours. In contrast, staining of SCC revealed a significant number of TGF-beta positive cells and the presence of extracellular matrix proteins.
  
  
  CONCLUSIONS
  The findings suggested that there is a positive correlation between histological differentiation, TGF-beta expression and the elaboration of extracellular matrix proteins.
authors.affiliation: Department of Oral Medicine and Pathology, Dental School of Thessaloniki, Aristotle University of Thessaloniki, Greece.
authors.forename: A K
authors.initials: AK
authors.lastname: Poulopoulos
authors.forename: I G
authors.initials: IG
authors.lastname: Kayavis
authors.forename: P
authors.initials: P
authors.lastname: Papanayotou
mesh_terms: D000818:Animals; D002294:Carcinoma, Squamous Cell / Q000378:metabolism*; D002454:Cell Differentiation / Q000502:physiology; D003094:Collagen / Q000096:biosynthesis; D004848:Epithelium / Q000378:metabolism; D016326:Extracellular Matrix Proteins / Q000096:biosynthesis*; D006801:Humans; D007150:Immunohistochemistry; D007797:Laminin / Q000096:biosynthesis; D008297:Male; D051379:Mice; D008819:Mice, Nude; D009061:Mouth Mucosa / Q000378:metabolism / Q000473:pathology; D051381:Rats; D017207:Rats, Sprague-Dawley; D016212:Transforming Growth Factor beta / Q000378:metabolism*; D014407:Tumor Cells, Cultured
chemical_list: D016326:Extracellular Matrix Proteins; D007797:Laminin; D016212:Transforming Growth Factor beta; D003094:Collagen