Mel-CAM Expression in Common Oral Carcinomas

Mel-CAM (CD146, MUC18) is a 113-kD heterophilic cell-cell adhesion glycoprotein found in normal and tumoral tissues.

The aim of this study is assessing the expression of Mel-CAM in common oral carcinomas like salivary gland mucoepidermoid carcinoma (MEC) and oral squamous cell carcinoma (OSCC) to differentiate the OSCC from high-grade MEC.

This study was performed on 19 specimens of MEC and 17 specimens of OSCC, which were retrieved from the archive of Department of Pathology of Taleghani Hospital, Tehran, Iran. Immunohistochemical staining was performed by using antibody against CD146. The data was analyzed by using SPSS software through Mann-Whitney, Spearman's correlation coefficient, and Kruskal-Wallis tests.

Mel-CAM was expressed in all MEC samples and 10 OSCC cases. The two groups were significantly different regarding the CD146 expression (p= 0.035). Furthermore, the CD146 expression was found to be significantly correlated with the invasion mode (p= 0.002), tumor size (p= 0.012), and histologic grade (p= 0.024) in OSCC group. No significant correlation existed between the expression, intensity and location with the histologic grade of MEC (p> 0.05). Nor was any significant correlation detected between the CD146 expression and lymph node metastasis in neither group.

Regarding the significant correlation between the CD146 expression and the prognostic factors in OSCC, this marker may predict the prognosis in OSCC patients, but not the MEC lesions. It cannot be used for differentiating high-grade MEC and OSCC.