title: Role of cyclins D1 and D3 in vestibular schwannoma.
abstract: BACKGROUND
  Vestibular schwannomas in younger patients have been observed to be larger in size and grow more quickly.
  
  
  OBJECTIVE
  This study aimed to evaluate the expression of three important cell cycle proteins, cyclin D1, cyclin D3 and Ki-67, in vestibular schwannoma patients separated into two age groups: ≤ 40 years or > 40 years.
  
  
  METHODS
  Immunohistochemical detection of cyclin D1, cyclin D3 and Ki-67 was undertaken in 180 surgically resected vestibular schwannomas.
  
  
  RESULTS
  The proliferation index of vestibular schwannomas was statistically higher in the ≤ 40 years age group compared to that in the > 40 years age group (mean of 4.52 vs 3.27, respectively; p = 0.01). Overexpression of cyclin D1 and cyclin D3 was found in 68 per cent and 44 per cent of tumours, respectively.
  
  
  CONCLUSIONS
  There was an increased Ki-67 proliferation index in the younger age group that appears to correlate with clinical behaviour. Vestibular schwannomas in both age groups show increased expression of cyclin D1 and cyclin D3.
authors.affiliation: University of Notre Dame Australia School of Medicine,Sydney,New South Wales,Australia.
authors.forename: J
authors.initials: J
authors.lastname: Jabbour
authors.affiliation: Department of Anatomical Pathology,SydPath,Sydney,New South Wales,Australia.
authors.forename: P
authors.initials: P
authors.lastname: Earls
authors.affiliation: Department of Otorhinolaryngology,St Vincent's Clinic,Sydney,New South Wales,Australia.
authors.forename: N
authors.initials: N
authors.lastname: Biggs
authors.affiliation: Department of Anatomical Pathology,SydPath,Sydney,New South Wales,Australia.
authors.forename: G
authors.initials: G
authors.lastname: Gracie
authors.affiliation: Department of Otorhinolaryngology,St Vincent's Clinic,Sydney,New South Wales,Australia.
authors.forename: P
authors.initials: P
authors.lastname: Fagan
authors.affiliation: University of Notre Dame Australia School of Medicine,Sydney,New South Wales,Australia.
authors.forename: R
authors.initials: R
authors.lastname: Bova
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D019938:Cyclin D1 / Q000378:metabolism*; D056743:Cyclin D3 / Q000378:metabolism*; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D019394:Ki-67 Antigen / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D009363:Neoplasm Proteins / Q000378:metabolism*; D009464:Neuroma, Acoustic / Q000235:genetics*; D055815:Young Adult
chemical_list: C530104:CCND1 protein, human; D056743:Cyclin D3; D019394:Ki-67 Antigen; D009363:Neoplasm Proteins; D019938:Cyclin D1
keywords: Acoustic Neuroma; Age Of Onset; Cyclin D1; Cyclin D3; Ki-67 Antigen; Neurofibromatosis 2