MUC4 and familial pancreatic carcinoma: Much work has been done looking at MUC4 overexpression in pancreatic cancer, where the NIDO domain is thought to play a key role in metastases.67 Through its extracellular EGF‐like domain, MUC4 interacts with the receptor tyrosine kinase, ErbB2, and controls ErbB2 and ErbB3 tyrosine phosphorylation.