title: RASSF1A protein expression and correlation with clinicopathological parameters in renal cell carcinoma.
abstract: BACKGROUND
  Epigenetic silencing of RAS association family 1A (RASSF1A) tumor suppressor gene occurs in various histological subtypes of renal cell carcinoma (RCC) but RASSF1A protein expression in clear cell RCC as well as a possible correlation with clinicopathological parameters of patients has not been analyzed at yet.
  
  
  METHODS
  318 primary clear cell carcinomas were analyzed using tissue microarray analysis and immunohistochemistry. Survival analysis was carried out for 187 patients considering a follow-up period of 2-240 month.
  
  
  RESULTS
  Expression of RASSF1A was found to be significantly decreased in tumoral cells when compared to normal tubular epithelial cells. RASSF1A immunopositivity was significantly associated with pT stage, group stage and histological grade of tumors and showed a tendency for impaired survival in Kaplan-Meier analysis.
  
  
  CONCLUSIONS
  While most tumors demonstrate a loss of RASSF1A protein, a subset of tumors was identified to exhibit substantial RASSF1A protein expression and show increased tumor progression. Thus RCC tumorigenesis without depletion of RASSF1A may be associated with an adverse clinical outcome.
authors.affiliation: Department of Urology, Medizinische Hochschule Hannover, Hannover, Germany. tezval.hossein@mh-hannover.de
authors.forename: Hossein
authors.initials: H
authors.lastname: Tezval
authors.forename: Axel S
authors.initials: AS
authors.lastname: Merseburger
authors.forename: Ira
authors.initials: I
authors.lastname: Matuschek
authors.forename: Stefan
authors.initials: S
authors.lastname: Machtens
authors.forename: Markus A
authors.initials: MA
authors.lastname: Kuczyk
authors.forename: Jürgen
authors.initials: J
authors.lastname: Serth
mesh_terms: D014408:Biomarkers, Tumor / Q000032:analysis*; D005260:Female; D006801:Humans; D007680:Kidney Neoplasms / Q000175:diagnosis* / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D009363:Neoplasm Proteins / Q000032:analysis*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013223:Statistics as Topic; D025521:Tumor Suppressor Proteins / Q000032:analysis*
chemical_list: D014408:Biomarkers, Tumor; D009363:Neoplasm Proteins; C411762:RASSF1 protein, human; D025521:Tumor Suppressor Proteins