E-cadherin and ß-catenin expression in well-differentiated and moderately-differentiated oral squamous cell carcinoma: relations with clinical variables.

The aim of this study was to establish the expression and localisation of E-cadherin and ß-catenin in oral squamous cell carcinomas (SCC) so that we could correlate the findings with prognostically-relevant clinicopathological variables. E-cadherin and ß-catenin expression in normal oral mucosa and in oral squamous cell carcinomas were examined immunohistochemically, and their association with clinicopathological factors and prognosis were then analysed in 69 patients who had been operated on for oral SCC. E-cadherin expression was found in all 69 cases: in 11 cases (16%) it was weak; in 21 (30%) moderate, and in 37 (54%) high. ß-Catenin expression was found in 64 cases (93%): in 18 cases (26%) cell-membrane expression was weak; in 26 (38%) it was moderate; in 19 (28%) it was high, and in one case (1%) there was cytoplasmic staining. No nuclear staining was detected. E-cadherin was significantly associated with histological grade (p=0.002) and alcohol consumption (p=0.05), and ß-catenin was significantly associated with nodal stage (p=0.02), TNM stage (p=0.009), and E-cadherin expression (p=0.01). However, none of them were independent prognostic factors in the disease-specific survival analysis. E-cadherin is closely linked to ß-catenin expression in oral SCC and to tumour differentiation. Alcohol consumption could increase the aggressiveness of SCC, leading to reduced expression of E-cadherin. ß-catenin could be an early marker for the identification of occult metastases in patients with oral SCC.

Focal adhesion kinase overexpression: correlation with lymph node metastasis and shorter survival in oral squamous cell carcinoma.

BACKGROUND: Focal adhesion kinase (FAK) has been identified as a key mediator in tumor progression. The objective of this study was to determine the role of FAK as a predictor of neck node metastasis and poor prognosis in oral squamous cell carcinomas (OSCCs). METHODS: FAK expression in normal oral mucosa and in 69 OSCCs was examined by immunohistochemistry, and the percentage of stained cells was recorded. The correlation of these findings with clinicopathologic variables and survival was studied. RESULTS: FAK expression in OSCCs was heterogeneous: 33.3% of cases showed weak expression; 23.2%, moderate expression, and 33.3% cases showed high expression. FAK expression significantly correlated with tumor size (p = .010), neck node metastasis (p = .01), and local tumor recurrence (p = .01). FAK expression was an independent prognostic factor in the survival analysis (p = .017). CONCLUSIONS: Increased expression of FAK may play a role in invasiveness and metastasis of OSCCs, which contribute to poor prognosis and low survival.