The cyclooxygenase-2 (COX-2) enzyme is overexpressed in different types of tumors and is known to be associated with malignant behavior of tumors. We determined the association of COX-2 expression and different grades of human meningioma.
This retrospective study was conducted on specimens obtained from adult patients with meningioma. Meningioma was classified according to the WHO 2007 classification protocol (I, II, and III). COX-2 expression intensity was scored based on the percentage of immunopositive cells as 0: 0-10%; +1: >10% and a part of the cell membrane; +2: >10% and complete cell membrane; and +3: >30% and complete cell membrane. Scores of +2 or +3 were considered as COX-2 positive.
Ninety meningioma cases (mean age = 53.0 ± 13.2 years, 71.1% female) were studied. COX-2 was positive in 25% (17/68), 68.4% (13/19), and 100% (3/3) of cases with tumor grade I, II, and III, respectively ( P < 0.001). There was a significant correlation between tumor grade and COX-2 expression score (Spearman's correlation coefficient = 0.422, P < 0.001).
There is a strong association between COX-2 expression and tumoral grade in meningioma with more aggressive tumors expressing COX-2 with more intensity. Prospective studies examining the association of COX-2 expression with tumor recurrence and interventional studies examining the role of COX-2 inhibitors anticancer therapy of meningioma are warranted.