Expression of urokinase-type plasminogen activator and its receptor in squamous cell carcinoma of the oral tongue

Abstract Urokinase-type plasminogen activator (uPA) and its receptor (uPAR) act in the proteolysis of basement membrane and extracellular matrix structures, facilitating tumor invasion. The purpose of this study was to evaluate the relationship between these proteins and clinicopathological parameters in squamous cell carcinoma of the oral tongue (SCCOT). Sixty cases of SCCOT were submitted to immunohistochemistry and analyzed semiquantitatively at the invasion front and in the tumor core. The results were associated with lymph node metastasis, clinical stage, locoregional recurrence, clinical outcome and histological grade of malignancy. A higher expression of uPA was observed in cases of tumors of high-grade versus low-grade malignancy (p = 0.010). Moreover, the cases with the worst pattern of invasion presented an overexpression of uPA (p = 0.011). The presence of locoregional recurrence was associated with uPAR (p = 0.039), and the expression of both biomarkers was much higher at the invasion front than in the tumor core (p < 0.001). The results suggest uPA and uPAR are involved in the progression and aggressiveness of SCCOT, mainly at the tumor-host interface.

Immunohistochemical expression of E-cadherin and CD44v6 in squamous cell carcinomas of the lower lip and tongue

This study analyzed the immunohistochemical expression of E-cadherin and CD44v6 in 15 squamous cell carcinomas (SCCs) of lower lip and 15 SCCs of tongue in order to verify a possible association between these proteins and the anatomic location of the lesion, nodal metastasis and histological grading of malignancy. The pattern of expression and number of immunopositive cells were evaluated. The results were analyzed with the Fisher's exact test, Mann-Whitney test and Spearman's Correlation Coefficient (r). using the SPSS software 10.0 for Windows. Statistical significance was set at 5 percent determined for a p-value<0.05 for all tests. There was no significant difference (p>0.05) in the pattern of expression and number of immunopositive cells for E-cadherin and CD44v6, regarding the anatomical location and nodal metastasis. For the histological grading, low score SCCs showed higher immunopositivity for E-cadherin and CD44v6, both for the pattern of expression and number of immunopositive cells (p<0.05). There was a negative correlation between the total score of malignancy and the pattern of expression and number of immunopositive cells for E-cadherin and CD44v6 (p<0.05). In conclusion, SCCs of the lower lip and tongue did not reveal significant differences in the expression of E-cadherin and CD44v6. The expression of these adhesion molecules revealed association only with tumor histological grading of malignancy. Therefore, these results suggest that E-cadherin and CD44v6 may not help elucidating the differences between the biological behavior of SCCs of the lower lip and tongue.

Este estudo analisou a expressão imuno-histoquímica de E-caderina e CD44v6 em 15 carcinomas de células escamosas (CCEs) de lábio inferior e em 15 CCEs de língua, com o intuito de identificar possíveis associações entre a expressão destas proteínas e a localização anatômica da lesão, ocorrência de metástase nodal e gradação histológica de malignidade. Foram avaliados o padrão de expressão e o número de células imunopositivas. Os resultados foram analisados pelo teste exato de Fisher, teste de Mann-Withney e coeficiente de correlação de Spearman (r), utilizando o software SPSS 10.0 para Windows. Para todos os testes, a significância estatística foi determinada em 5 por cento, para um valor de p<0,05. Os resultados revelaram não haver diferença significativa no padrão de expressão e na quantidade de células imunopositivas para E-caderina e CD44v6 em relação à localização anatômica e metástase nodal (p>0,05). Para a gradação histológica de malignidade, os CCEs de baixo escore revelaram maior imunopositividade para E-caderina e CD44v6, tanto para o padrão de expressão quanto para o número de células imunopositivas (p<0,05). Observou-se correlação negativa entre o escore total de malignidade e o padrão de expressão e a quantidade de células imunopositivas para E-caderina e CD44v6 (p<0,05). Em conclusão, CCEs de lábio inferior e língua não revelaram diferenças significativas na expressão de E-caderina e CD44v6. A expressão destas moléculas de adesão revelou associação apenas com gradação histológica de malignidade dos CCEs. Dessa forma, os resultados sugerem que E-caderina e CD44v6 podem não ser capazes de elucidar as diferenças existentes no comportamento biológico de CCEs de lábio inferior e língua.

Benign Peripheral Nerve Sheath Tumor of the Tongue

Peripheral nerve sheath tumors rarely occur in the oral cavity and include neurofibroma, schwannoma, and palisaded encapsulated neuroma. We report a rare case of benign peripheral nerve sheath tumor of the tongue. This tumor was a 0.8 x 0.5 cm sized, firm mass on the left lateral surface of the tongue. Histologically, this mass was composed of well- circumscribed variable sized nodules, which consisted of moderately cellular spindle cells with vague nuclear palisading and a small amount of fibrous tissue. Most of the tumor cells were strongly positive for S-100 protein, but negative for epithelial membrane antigen on immunohistochemistry. No axons were found by immunostaining for neurofilament and Bodian stains. In addition, the surrounding, compressed, fibrous tissue showed rare EMA- positive cells. The present case might be a rare case of neurofibroma arising in the tongue, although immunohistochemical and special stains did not support such a diagnosis.