We studied 109 malignant mesotheliomas (58 epithelioid, 26 sarcomatoid, and 25 biphasic) by immunohistochemistry and qRT-PCR analysis, and demonstrated a substantial switch from epithelial markers (E-cadherin, β-catenin, and cytokeratins 5/6) to mesenchymal markers (N-cadherin, vimentin, α-smooth muscle actin, Snail, Slug, Twist, ZEB1, ZEB2, S100A4, MMP2, and MMP9) through epithelioid to biphasic and sarcomatoid histotypes.
B72.3, Ber-EP4, carcinoembryonic antigen, and vimentin are useful immunohistochemical markers in differentiating malignant mesotheliomas from adenocarcinomas, whereas immunohistochemistry does not reliably distinguish malignant from benign hyperplastic mesothelial cells.