MUC5AC and familial pancreatic carcinoma: In this context, the membrane-bound mucin MUC4, which is expressed as early as in PanIN-1A whereas it is not expressed in the healthy pancreas, and its membrane partner the oncogenic receptor ErbB2 which is frequently overexpressed in pancreatic cancer as well as in PanINs, represent promising therapeutic targets [3], [4], [5], [6].