E-cadherin loss and Delta Np73L expression in oral squamous cell carcinomas showing aggressive behavior

Purpose: The present paper sought investigate the existence of parameters useful for predicting lymph node metastases in cases of surgically resected oral squamous cell carcinomas (OSCC). Fifty-eight cases were studied for E-Cadherin and the truncated dominant-negative isoform of p63 (Np63) with immunohistochemistry. In addition, the p63 gene expression profile was evaluated by RT-PCR to disclose the presence of the truncated variant Np73L. Results: E-Cadherin expression was the most powerful parameter related to the presence of lymph node metastases at presentation. Twenty-four cases out of 38 (63%) showing low E-Cadherin expression had lymph node metastases at presentation as compared to 5 out of 20 (25%) ( P<0.01) cases showing high E-Cadherin expression. The high predictive value was also maintained when a low expression of E-Cadherin was associated immunohistochemical high expression of Np63. The association between low E-Cadherin expression and Np73L (as seen with RT-PCR) was highly predictive for developing lymph node metastases, especially in small tumours (T1T2). When this association occurred, metastases developed in 62.5% of cases during the follow-up as compared to 16.1% in those which did not show low E-Cadherin expression and a Np73L presence. Conclusion: The present study shows that low E-Cadherin expression is useful for predicting lymph node metastases in cases of OSCC. The predictive value is enhanced when low E-Cadherin positivity is associated with Np63 and Np73L expression.