role of cyclooxygenese-2 (cox-2) expression in breast cancer differentiation and its relationship with hormone receptors status

background and objectives: cyclooxygenese-2 (cox-2) expression in breast cancer and its correlation with tumor prognosis is unclear. we investigated the incidence of cox-2 expression in patients and assessed interactions between cox-2 and clinical features of cancer and expression of her2/neu, estrogen receptor (er), and progesterone receptor (pr). methods: cox-2 expression was investigated by immunohistochemistry in 29 patients’ specimens diagnosed as primary breast cancer between 2006 and 2008 at the fatemieh hospital, semnan, iran. relationship between cox-2 expression and age, histological grade, histological type, nodal status, and hormone receptor status were evaluated. results: we used ihc method although it was not a quantitative study. its expression depends on quality of antibody, staining and selection of analyzed region. cox-2, her-2, er, and pr were detected in 89.7%, 51.7%, 82.8%, and 79.3% of samples, respectively. elevated cox-2 expression was not associated with size and grade of tumor, while mean numbers of involved lymph nodes was significantly higher in those with elevated expression of cox-2 (p = 0.001). there were no significant correlations between cox-2 expression and her-2, er, and pr receptors. conclusion: only tumor tissue was analyzed and did not compare to normal tissue. elevated cox-2 expression can be found in most patients with breast cancer and has a crucial role in tumor differentiation regarding degree of lymph node involvement. it seems that correlation between cox-2 and other oncogens and hormonal receptors might be influenced by geographical and racial factors, so, assessment of these relationships in each patient's population may be necessary.