PTX3 and pancreatic neoplasm: Furthermore, in a phase I clinical trial targeting stroma with ATRA along with standard chemotherapy24 for patients with pancreatic cancer (STARPAC: NCT03307148) we demonstrate that within 5 h after the first dose of ATRA (cycle 1 day 1) there is a significant immediate PTX3 response (increased serum level) in patients with stable disease (non-progressors = stable disease and partial responders) but not in those who eventually have progressive disease (Fig. 5E), with good correlation between serum PTX3 levels and tissue PTX3 expression (Supplementary Fig. 8).