title: Cyclooxygenase-2 supports tumor proliferation in vestibular schwannomas.
abstract: BACKGROUND
  Recent studies have shown that cyclooxygenase-2 (COX-2) plays an important role in tumor growth and neovascularization. However, COX-2 expression in vestibular schwannomas (VSs) has not been investigated.
  
  
  OBJECTIVE
  To analyze the pattern of COX-2 expression in sporadic and neurofibromatosis type 2 (NF2)-associated VSs and its relationship with tumor proliferation and microvessel density.
  
  
  METHODS
  Fifteen sporadic and 15 NF2-associated VSs were examined for COX-2 expression, microvessel density, and proliferation rate by immunohistochemical methods. Immunohistochemical scores were used to interpret the extent and intensity of COX-2 staining. Microvessel density (MVD) was determined using von Willebrand factor (vWf). Proliferation rate was quantified using Ki-67. The relationship among COX-2 expression, MVD, and proliferation rate was statistically analyzed.
  
  
  RESULTS
  COX-2 expression was detected in 29 (96.67%) of 30 VSs, with no significant difference between sporadic and NF2-associated VSs (P = .722). In 6 (20%) VSs, COX-2 expression was graded as strong, in 12 (40%) as moderate, and in 11 (36.7%) as weak. VSs with high proliferation showed significantly higher COX-2 expression (P = .015) than VSs with low proliferation. COX-2 expression and MVD did not show specific biological correlations (P = .035).
  
  
  CONCLUSIONS
  Our data demonstrate that COX-2 is expressed in VSs. High COX-2 expression in VSs with high proliferation rates suggests that the COX-2 pathway may be involved in the development and growth of VSs.
authors.affiliation: Department of Neurosurgery, Hannover Medical School, Hannover, Germany. hong.bujung@mh-hannover.de
authors.forename: Bujung
authors.initials: B
authors.lastname: Hong
authors.forename: Claudia A
authors.initials: CA
authors.lastname: Krusche
authors.forename: Kerstin
authors.initials: K
authors.lastname: Schwabe
authors.forename: Sabrina
authors.initials: S
authors.lastname: Friedrich
authors.forename: Rüdiger
authors.initials: R
authors.lastname: Klein
authors.forename: Joachim K
authors.initials: JK
authors.lastname: Krauss
authors.forename: Makoto
authors.initials: M
authors.lastname: Nakamura
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D049109:Cell Proliferation; D051546:Cyclooxygenase 2 / Q000502:physiology*; D005260:Female; D015971:Gene Expression Regulation, Enzymologic; D006801:Humans; D008297:Male; D008875:Middle Aged; D009389:Neovascularization, Pathologic / Q000201:enzymology / Q000473:pathology; D016518:Neurofibromatosis 2 / Q000201:enzymology / Q000473:pathology; D009464:Neuroma, Acoustic / Q000201:enzymology* / Q000473:pathology*; D055815:Young Adult
chemical_list: D051546:Cyclooxygenase 2; C496540:PTGS2 protein, human