Immunohistochemical Array for Clear Cell Type Mucoepidermoid Carcinoma

Background : The protein expression profile of clear cell type mucoepidermoid carcinoma (MEC) is not well known. Methods : We examined a case of clear cell type MEC by immunohistochemical (IHC) array using 59 antibodies against oncoproteins, proliferation-related proteins, apoptosis-related proteins, growth factor-related proteins, angiogenesis-related proteins, and matrix proteins. Results : MEC tumor cells showed 40 to 60% more expression of BCL-2 and cyclin-dependent kinase 4 than normal gingival tissue, and 20-40% more expression of BCL-2-associated agonist of cell death, deleted in malignant brain tumors 1, E-cadherin, eIF5A, hypoxia-inducible factor, vimentin, and Wnt-1. Expression of other proteins, including p53, epidermal growth factor receptor, proliferating cell nuclear antigen, survivin, carcinoembryonic antigen, beta-catenin, poly-ADP ribose-polymerase, etc. were relatively weak in MEC tumor cells. Conclusions : The IHC array for our MEC contained strong oncogenic signals involving Wnt-1/adenomatous polyposis coli, tumor necrosis factor alpha/signal transducer and activator of transcription 3/BCL-2, and pAKT pathways, signals that could result in the prolonged survival of clear tumor cells.