The locoregional activity of MUC5AC and its importance within pancreatic adenocarcinoma is related to different metabolic pathways that favour metastatic dissemination (e.g., activation of ERK and VEGFR1 or promotion of the activation of metalloproteases and integrins), and it is related to chemoresistance mechanisms to gemcitabine via deregulation of the E-cadherin/β-catenin axis [36,37,38,39]. The gene discussed is MUC5AC; the disease is pancreatic adenocarcinoma.