Lymphoblastic T-cell lymphoma in mice is unaffected by Celecoxib as single agent or in combination with cyclophosphamide.

Celecoxib, an inhibitor of cyclooxygenase-2, is a promising novel antitumor agent with pleitropic mechanisms of action. Whereas this drug induces growth arrest and apoptosis of B-lymphoma cells, its effect against aggressive T-cell neoplasms remains to be studied. We therefore evaluated Celecoxib therapy of immunocompetent mice transplanted with lymphoblastic T-cell lymphomas. Oral Celecoxib in clinically relevant and non-toxic doses did not affect the degree of hypersplenism or the number of viable lymphoma cells. The clinical deterioration of Celecoxib-treated mice was not different from untreated controls. The impact of adding Celecoxib (60 mg/kg) to cyclophosphamide (200 mg/kg x 1, i.p.) was assessed but showed no benefit compared to cyclophosphamide alone. Thus, Celecoxib lacks effect against lymphoblastic T-cell lymphoma in mice.