An immunohistochemical study of cyclooxygenase-2 expression in canine multicentric lymphoma

Cyclooxygenase-2 (COX-2) expression has been associated with development and progression in spontaneous human and dogs tumors. Studies demonstrated that non-steroidal anti-inflammatory drugs, which inhibit COX enzyme, may be used in the treatment of some tumors. Lymphoma is a systemic disease and the most common hematological malignancy in dogs. There are few studies about COX-2 expression in human and canine lymphoma. In this study, immunohistochemical evaluation for COX-2 expression was performed in 12 dogs with multicentric lymphoma. The diagnosis was confirmed by histopathological examination. Six samples of normal lymph nodes were either used in the study. No COX-2 immunoreactivity was detected in all samples from canine lymphoma and normal lymph nodes, as well previous studies in canine lymphoma.