title: EGFR protein overexpression correlates with chromosome 7 polysomy and poor prognostic parameters in clear cell renal cell carcinoma.
abstract: BACKGROUND
  The role of epidermal growth factor (EGF) and its receptor (EGFR) in the pathogenesis and progression of various malignant tumors has long been known, but there is still disagreement concerning prognostic significance of EGFR expression in clear cell renal cell carcinoma (CCRCC). The present study was designed to analyze more objectively the protein EGFR expression in CCRCC and to compare its value with EGFR gene copy number changes and clinicopathologic characteristics including patient survival.
  
  
  METHODS
  The protein EGFR expression was analyzed immunohistochemically on 94 CCRCC, and gene copy number alterations of EGFR by FISH analysis on 41 CCRCC selected according to distinct membrane EGFR staining.
  
  
  RESULTS
  Membrane EGFR expression in tumor cells was heterogeneous with respect to the proportion of positive cells and staining intensity. FISH analysis did not reveal EGFR gene amplification, while polysomy of chromosome 7 found in 41% was associated with higher EGFR membrane expression. Moreover, EGFR overexpression was associated with a higher nuclear grade, larger tumor size and shorter patient's survival, while there was no connection with pathological stage.
  
  
  CONCLUSIONS
  In conclusion, the protein expression of EGFR had an impact on prognosis in patients with CCRCC, while an increased copy number of chromosome 7 could be the possible reason for EGFR protein overexpression in the absence of gene amplification.
authors.affiliation: Department of Pathology, School of Medicine, University of Rijeka, B, Branchetta 20, Rijeka 51000, Croatia.
authors.forename: Gordana
authors.initials: G
authors.lastname: Dorđević
authors.forename: Koviljka
authors.initials: K
authors.lastname: Matušan Ilijaš
authors.forename: Ita
authors.initials: I
authors.lastname: Hadžisejdić
authors.forename: Anton
authors.initials: A
authors.lastname: Maričić
authors.forename: Blaženka
authors.initials: B
authors.lastname: Grahovac
authors.forename: Nives
authors.initials: N
authors.lastname: Jonjić
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002292:Carcinoma, Renal Cell / Q000235:genetics / Q000378:metabolism* / Q000401:mortality* / Q000473:pathology; D002897:Chromosomes, Human, Pair 7 / Q000235:genetics / Q000378:metabolism*; D018572:Disease-Free Survival; D066246:ErbB Receptors / Q000096:biosynthesis* / Q000235:genetics; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D007150:Immunohistochemistry; D007680:Kidney Neoplasms / Q000235:genetics / Q000378:metabolism* / Q000401:mortality* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009363:Neoplasm Proteins / Q000096:biosynthesis* / Q000235:genetics; D011123:Polyploidy; D012189:Retrospective Studies; D015996:Survival Rate
chemical_list: D009363:Neoplasm Proteins; C512478:EGFR protein, human; D066246:ErbB Receptors