Keratin 20 (KRT20) - Epithelial cell marker used for differential diagnostics of cancer

The keratin gene family is a large group of intermediate filament and structural proteins that provide the structural components of hair, nails, horns, scales, claws and similar types of hard tissues. Keratins are also important for intracellular stability in epithelial tissues and different keratins often display organ- or tissue specific expression patterns. Due to these specific expression patterns, keratins are often used as diagnostic biomarkers. Keratin 20 is a type I keratin expressed in simple epithelia and primarily expressed by glandular cells of gastrointestinal tract (stomach, duodenum, small intestine, colon and rectum) and is used for diagnostic purposes to identify cancers originating from the gastrointestinal tract, especially cancers of colorectal origin.