ENO1 and pancreatic ductal adenocarcinoma: Post-translational modifications contribute to the generation of ENO1 autoantibodies, as evidenced by the observation that patients with pancreatic ductal adenocarcinoma (PDA) produce antibodies that specifically target epitopes containing phosphorylated serine 419 within the plasminogen binding domain of ENO1 (Figure 1), and correlate with improved outcome in patients receiving chemotherapy, suggesting a protective role (Tomaino et al., 2011).