Moreover, the cell surface proteoglycan glypican-1 (GPC-1) is also found in exosomes extracted from pancreatic and breast cancer patients (Lorenzon and Blandino, 2016; Wang et al., 2019b), which can also be detected in the early and late stages of pancreatic cancer compared to the serum of healthy controls. Here, GPC1 is linked to familial pancreatic carcinoma.