MUC1 and pancreatic ductal adenocarcinoma: Additionally, it has been discovered that in pancreatic ductal adenocarcinoma (PDAC), MUC1 overexpression induces non-canonical TGF-β signaling, where MUC1 overexpression activates the JNK pathway in response to TGF-β, thus altering its function from a tumor suppressor to a tumor promoter (64).