Combined Exosomal GPC1, CD82, and Serum CA19-9 as Multiplex Targets: A Specific, Sensitive, and Reproducible Detection Panel for the Diagnosis of Pancreatic Cancer

Pancreatic cancer is a highly lethal malignancy with poor prognosis due to the lack of early symptoms and resultant late diagnosis. Thus, it is extremely urgent to establish a simple and effective method for the early diagnosis of pancreatic cancer. Although some studies have provided positive evidence for the use of exosomal surface protein glypican-1 (GPC1) as a biomarker for early screening, its clinical application is still controversial. Here, we systematically verified the role of exosomal GPC1 as a potential screening biomarker. First, bottleneck problems of a stable detection method and an identification standard were systematically studied, and a Python-based standardized data processing method was established to analyze exosomal GPC1 expression. Second, a detection panel consisting of exosomal GPC1, exosomal cluster of differentiation 82 (CD82), and serum carbohydrate antigen 19-9 (CA19-9) was employed for pancreatic cancer detection. This panel exhibited excellent diagnostic results (AUC = 0.942) and could effectively distinguish healthy people from patients with pancreatic cancer (P value threshold = 0.2282) and patients with pancreatitis from patients with pancreatic cancer (P value threshold = 0.5467). Implications: These results indicate that the combined detection of exosomal GPC1, exosomal CD82, and serum CA19-9 shows great promise as a standard method for pancreatic cancer detection and that this panel could be further applied for screening pancreatic cancer in Chinese populations.