Villin is part of cytoskeleton associated with the microvillar actin core bundle of gastrointestinal and renal brush border. It can interact with actin in a Ca2+ and phosphoinositide-regulated manner. Villin is a very specific marker for adenocarcinomas of the gastrointestinal tract and the pancreas. It is also expressed in some Merkel cell tumor and adenocarcinoma of the lung, prostate, ovarian and kidney.
