Expression of Nonsteroidal Anti-Inflammatory Drug-Activated Gene(NAG-1)as a Prognostic Marker in Oral Tongue Squamous Cell Carcinoma

Background and Objectives：Our previous study showed that nonsteroidal anti-inflammatory drug-activated gene (NAG-1) induced apoptosis in tongue cancer cells. However, the NAG-1 expression in tongue cancer and normal tissues was not studied. The aim of this study was to investigate the expression of NAG-1 in oral tongue cancer and normal tissues and to identify the relationship between NAG-1 expression and the prognosis of tongue cancer patients to determine whether NAG-1 can be used as a valuable prognostic marker in tongue cancer. Subjects and Method：The medical records and pathologic reports of 42 tongue cancer patients who received surgery as primary treatment were surveyed. Tongue cancer and normal tissues, which were obtained during the operation, were stained with anti-NAG-1 antibody using the immunohistochemical method and the H-score was calculated. Results：As a result, the higher expression of NAG-1 was observed in the cancer tissues than in the normal tissues. NAG-1 expression was noted to be higher in cases of tongue cancers with more invasion, positive lymph node metastasis, and poor prognosis. A 5-year survival rate was significantly decreased in cases showing higher NAG-1 expression in the cancer tissues than in the normal tissues. Conclusion：The higher NAG-1 expression in the cancer tissue suggests malignant changes in cancer tissue and poor prognosis. Therefore, NAG-1 may be a useful prognostic marker in tongue squamous cell carcinoma.ope