title: Expression of COX-2, PCNA, Ki-67 and p53 in gastrointestinal stromal tumors and its relationship with histopathological parameters.
abstract: OBJECTIVE
  To investigate the expression of Cyclooxygenase-2 (COX-2), proliferating cell nuclear antigen (PCNA), Ki-67 and p53 in gastrointestinal stromal tumors (GISTs) and its relationship with histopathological parameters.
  
  
  METHODS
  Twenty-five GISTs were examined by light microscopy and immunohistochemistry. c-kit, CD34, SMA, S-100 protein, COX-2, PCNA, Ki-67 and p53 were detected immunohistochemically and the relationship was evaluated among histopathologic parameters such as mitotic index (MI), tumor grade, tumor size, COX-2, PCNA, Ki-67 and p53.
  
  
  RESULTS
  COX-2 protein expression was found in 19 of 25 (76%) of the tumors, and expression was noted in the cytoplasm of the tumor cells. p53 was significantly related to MI and tumor grade but no relationship was found between COX-2, proliferation markers and MI, tumor grade and tumor size.
  
  
  CONCLUSIONS
  COX-2 is expressed in most GISTs and it may play an important role in the proliferation and progression of these tumors or a useful marker to identify GIST. Although immunohistochemical assessment of p53 can be used for distinguishing the risk groups of GISTs, tumor size and mitotic rate should be considered at the same time.
authors.affiliation: Department of Pathology of Affiliated Hospital, Faculty of Medicine, Cukurova University, Adana 01330, Turkey. gumurdulu@yahoo.com
authors.forename: Derya
authors.initials: D
authors.lastname: Gumurdulu
authors.forename: Seyda
authors.initials: S
authors.lastname: Erdogan
authors.forename: Fazilet
authors.initials: F
authors.lastname: Kayaselcuk
authors.forename: Gulsah
authors.initials: G
authors.lastname: Seydaoglu
authors.forename: Cem-K
authors.initials: CK
authors.lastname: Parsak
authors.forename: Orhan
authors.initials: O
authors.lastname: Demircan
authors.forename: Ilhan
authors.initials: I
authors.lastname: Tuncer
mesh_terms: D000199:Actins / Q000378:metabolism; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D018952:Antigens, CD34 / Q000378:metabolism; D051546:Cyclooxygenase 2 / Q000378:metabolism*; D005260:Female; D046152:Gastrointestinal Stromal Tumors / Q000378:metabolism* / Q000473:pathology*; D006801:Humans; D019394:Ki-67 Antigen / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D008940:Mitotic Index; D018809:Proliferating Cell Nuclear Antigen / Q000378:metabolism*; D009418:S100 Proteins / Q000378:metabolism; D016159:Tumor Suppressor Protein p53 / Q000378:metabolism*
chemical_list: D000199:Actins; D018952:Antigens, CD34; D019394:Ki-67 Antigen; D018809:Proliferating Cell Nuclear Antigen; D009418:S100 Proteins; D016159:Tumor Suppressor Protein p53; D051546:Cyclooxygenase 2