PTPN18 and lung carcinoma: Results showed that PTPN3, PTPN7, PTPN12, and PTPN14 were expressed at higher levels, while expressions of PTPN1, PTPN5, PTPN6, PTPN9, PTPN12, PTPN13, PTPN18, PTPN21, and PTPN22 were downregulated in lung cancer.