Podoplanin is a 38 kDa type-1 transmembrane glycoprotein, widely used as a specific marker for lymphatic endothelial cells and lymphangiogenesis. In normal tissue, podoplanin is also expressed in kidney podocytes, skeletal muscle, placental, lung, heart, myofibroblasts, osteoblasts, mesothelial cells, and the basal layer of epidermis. In cancer tissue, podoplanin is upregulated in a variety of tumor types that include squamous cell carcinoma of the oral cavity, in the larynx, lung, cervix, esophagus, skin, and in mesothelioma, granulosa cell tumors, and tumors of the central nervous system.