Expression of COX-2, PCNA, Ki-67 and p53 in gastrointestinal stromal tumors and its relationship with histopathological parameters.
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.
Gumurdulu
Derya
D
Department of Pathology of Affiliated Hospital, Faculty of Medicine, Cukurova University, Adana 01330, Turkey. gumurdulu@yahoo.com
Erdogan
Seyda
S
Kayaselcuk
Fazilet
F
Seydaoglu
Gulsah
G
Parsak
Cem-K
CK
Demircan
Orhan
O
Tuncer
Ilhan
I
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*
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