Serum levels of iCAF-derived Osteoglycin predict favorable outcome in pancreatic cancer

Pancreatic ductal adenocarcinoma (PDAC) is characterized by abundant stroma, the main cellular constituents of which are cancer-associated fibroblasts (CAFs). Heterogeneity in the PDAC CAF population was recently delineated demonstrating that both tumor-promoting and -suppressive activities co-exist in the stroma. Here, we aimed to identify biomarkers for the CAF population that contribute to a favorable outcome. Osteoglycin (OGN) was identified as a candidate serum prognostic marker. Single-cell analysis in KPC mice indicated that OGN is derived from a subgroup of inflammatory CAFs. OGN-expressing fibroblasts are distinct from resident healthy pancreatic stellate cells and arise during pancreatitis. Serum OGN levels were prognostic for favorable overall survival in two independent PDAC cohorts. Examination of single cell RNA expression profiles of pancreatic cells and post induced pancreatitis