[3,5,6] To determine the functional consequences of PTPRD mutation in HNSCC, we generated several representative HNSCC-derived PTPRD mutants by site-directed mutagenesis, including one mutation in the extracellular domain (S384R), one in the catalytic domain (K1502M), and two in the transmembrane region (T1100M and L1147F). The gene discussed is PTPRD; the disease is head and neck squamous cell carcinoma.