Objective:To study the growth inhibition and potential mechanisms of celecoxib on nasopharyngeal carcinoma CNE-2Z cell lines.Methods:The effect of celecoxib on the growth of CNE-2Z cells was evaluated by MTT assay.The expressions of proliferating cell nuclear antigen(PCNA)and cyclooxygenase-2(COX-2)were assessed by immunocytochemistry method.Cell cycle was measured by Flow cytometry(FCM).Results:Celecoxib inhibited the proliferation of CNE-2Z cells in dosage and time dependent manner.The cell cycle was arrested in G0/G1 phase in CNE-2Z cells treated with celecoxib;Immunocytochemistry showed that the expressions of PCNA and C0X-2 decreased after incubated with celecoxib for 48 hours.Conclusion:The expression of COX-2 is found in CNE-2Z cell lines.The growth of CNE-2Z cell 1ines can be inhibited by celecoxib.Celecoxib may be used as chemotherapeutic agent for nasopharyngeal carcinoma.