The expression of human PDPN (hPDPN) has been reported in several malignant tumors, including malignant brain tumors [[14], [15], [16], [17]], malignant mesotheliomas [18,19], oral squamous cell carcinomas [20], esophageal cancers [21], lung cancers [22], osteosarcomas [[23], [24], [25]], chondrosarcomas [24], and testicular tumors [26]. This evidence concerns the gene PDPN and cancer.