Immunoexpression of BRAF, EGFR and CD10 in ameloblastoma

The ameloblastoma is the most challenging odontogenic neoplasm to treat because of its locallyinvasive behaviour, severe clinical implication, risk of malignant transformation and high recurrence rate. Recent evidence suggests that BRAF, EGFR and CD10 have a role in the local invasiveness of ameloblastoma. However, the spatial distribution characteristics of these pro-invasive factors and their association with clinical parameters in this neoplasm are largely unexplored. We sought to address these issues in ameloblastoma subtypes and to determine their biological relevance. Nineteen unicystic (UA) and 20 conventional ameloblastoma (SMA) were subjected to immunohistochemical staining for BRAF, EGFR and CD10, and semiquantitative analysis was performed. All ameloblastoma cases (n=39/39; 100%) exhibited a BRAF+/EGFR+/CD10+immunoprofile. Their expression rates were significantly higher in SMA than UA (P<0.05). BRAF, essential for the progression and proliferation of ameloblastoma, was detected mainly in the cytoplasm of stellate reticulum-like>stromal>preameloblast- like cells (P<0.05). EGFR, a potent oncogenic protein, showed predominantly nuclear localisation. CD10, an apoptosis-inhibitory factor, was strongly expressed in the membrane of stellate reticulum-like cells. Taken together, present results suggest that the spatial distribution patterns of BRAF, EGFR and CD10 parallel the specific behaviours of SMA and UA. Their cellular and intracellular protein localisations have important targeted therapy implications.