Statement of Problem: Squamous cell carcinoma (SCC) is the most common cancer of the mouth, but its pathogenesis is unknown. HER2/neu is a protoncogene with homologue sequence with EGF. αSMA is a smooth muscle specific actin which indicates the existence of myofibroblasts in the oral cancer stroma.
Purpose: This study aimed to measure the frequency of Her2/neu and (alpha) αSMA in oral SCC.
Materials and Method: For this study, 18 paraffinized blocks of OSCC were immunostained with Anti HER2/neu, Anti (Alpha) SMA. Percentage and degree of the epithelial cells staining and percentage staining of myofibroblasts were considered. The results of the study were analyzed using kappa and X2.
Results: From 18 cases of OSCC, 3 and 12 cases were positive with HER2/neu and αSMA, respectively. In the normal oral mucosa, one case was positive (Score 2) with HER2/neu but αSMA positive myofibroblasts were not seen in the stroma of OSCC. A significant difference was seen in αSMA expression in OSCC and the normal oral mucosa ( p =0.002). No significant difference was found in HER2/neu expression in OSCC and normal mucosa
( p >0.05).
Conclusion: The results of this study suggest that αSMA has an effective role in pathogenesis and aggressive behavior of OSCC but HER2/neu has no main role in this type of oral cancer.