The expression of human PDPN (hPDPN; 162 amino acids) has been reported in many cancers, including oral cancers, malignant brain tumors, esophageal cancers, lung cancers, malignant mesotheliomas, bladder cancers, testicular tumors, and osteosarcomas [2, 4–16]. The gene discussed is PDPN; the disease is osteosarcoma.