The most useful mesothelial and epithelial markers proposed for the diagnosis of mesothelioma are a combination of markers, often including calretinin (a vitamin D-dependent calcium-binding protein involved in calcium signalling) [33], HBME-1, thrombomodulin, WT-1, mesothelin, and podoplanin as mesothelial markers, and pCEA, Ber-EP4, TTF-1, and TAG72 as epithelial markers [34]. The gene discussed is PDPN; the disease is mesothelioma.