CTSE and pancreatic ductal adenocarcinoma: Among them, TMPRSS4 was overexpressed in, and identified as a biomarker of, pancreatic carcinoma (33), TSPAN1, TMPRSS4, and CTSE are potential diagnostic or prognostic markers for pancreatic ductal adenocarcinoma (31, 33, 35), and most of these genes are associated with metastasis and proliferation and in pancreatic cancer.