Abstract
We previously reported on the detection of the heparin sulfate proteoglycan Glypican-1 (GPC1) on serum-derived exosomes in patients with pancreatic cancer and breast cancer1. GPC1 expression is elevated in several cancer types and associated with poor prognosis2,3, including in pancreas cancer cells, mouse and human pancreatic cancer4-9. Informed by genetic studies, GPC1 is proposed to control fibroblast growth factor (FGF) signaling in mouse brain development10, and may be critical for pancreatic cancer cell proliferation and VEGF-A induced pancreatic tumor angiogenic response5,6. The proteoglycan GPC1, GPI-anchored to the cell surface, acts as a co-receptor for several heparin binding growth factors, thereby implicating it in promoting tumor progression6-9,11.