Mesothelin (MSLN), a cell–surface glycoprotein, is a tumor-differentiation antigen that is highly expressed in mesothelioma (MPM), lung cancer, PC, and ovarian cancer.96–99 However, it is also expressed normally in the pleura, pericardium, and peritoneum mesothelial cells.100. The gene discussed is MSLN; the disease is lung carcinoma.