EXPRESSION OF METASTASIS ASSOCIATED PROTEIN 1 AS A POSSIBLE PROGNOSTIC INDICATOR IN ORAL SQUAMOUS CELL CARCINOMA

INTRODUCTION: Lymph node (LN) metastasis is one of the most important prognostic factors related to survival of oral squamous cell carcinoma (OSCC). Although, metastasis associated protein 1 (MTA1) overexpression is closely correlated with the metastasis of several human cancers, its role in determining lymph node metastases in OSCC patients remains undefined. Proliferating Cell Nuclear Antigen (PCNA) is the most representative proliferating marker; yet there is a controversy as to whether it can be used as a prognostic marker in OSCC. OBJECTIVES: To evaluate the immunoexpression of MTA1 and PCNA in metastatic versus non-metastatic OSCC; and correlate it with LN metastasis. MATERIALS AND METHODS: MTA1 and PCNA immunoexpression was detected immunohistochemically in 20 OSCC specimens; 10 of which had metastatic LNs and 10 with non-metastatic LNs (used as a control group). Their correlation with LN metastasis was evaluated. RESULTS: MTA1 immunoexpression showed significant correlation with LN metastasis but not with the histologic grade of the tumor. Whereas, PCNA immunoexpression revealed a significant correlation with the histologic grade of the tumor, but not with nodal metastasis. CONCLUSIONS: The present study suggests that MTA1 protein may have a clinical potential to be used as a prognostic factor to identify pathologically node-negative OSCC patients who may be at high risk to develop regional metastasis. On the other hand, PCNA is unlikely to play an important role in predicting LN metastasis in OSCC patients. KEYWORDS: OSCC, MTA1, PCNA, LN metastasis.