Cytokeratin 7 & CDX2 (EP16 & EP25), RMab

Summary and Explanation

Cytokeratin 7 (CK7) reacts with proteins that are found in most ductal, glandular and transitional epithelium of the urinary tract and bile duct epithelial cells. CK7 distinguishes between lung and breast epithelium that stain positive, and colon and prostate epithelial cells that are negative. CDX2 is a caudal-type homeobox gene that encodes an intestine-specific transcription factor expressed early in intestinal development and that may be involved in the regulation of proliferation and differentiation of intestinal epithelial cells.

The Cytokeratin 7 antibody has been shown to label the rete epithelium in the testis, epididymis epithelium, and the surface epithelium of the stomach and duodenum. Transitional-cell Carcinomas are positive and Prostate Cancers are negative. CDX2 antibody has been useful in distinguishing the gastrointestinal origin of Metastatic Adenocarcinomas and Carcinoids. A high percentage of Mucinous Carcinomas of the Ovary also stain positively with this antibody, as well as Carcinomas from the upper gastrointestinal tract.