Keratin 20

Keratin 20, often abbreviated CK20, is a is_associated_with::protein that in humans is encoded by the KRT20 is_associated_with::gene.

Keratin 20 is a is_associated_with::type I cytokeratin. It is a major cellular is_associated_with::protein of mature is_associated_with::enterocytes and is_associated_with::goblet cells and is specifically found in the gastric and intestinal is_associated_with::mucosa.

In is_associated_with::immunohistochemistry, antibodies to CK20 can be used to identify a range of is_associated_with::adenocarcinomata arising from epithelia that normally contain the CK20 protein. For example, the protein is commonly found in is_associated_with::colorectal cancer, is_associated_with::transitional cell carcinomas and in is_associated_with::Merkel cell carcinoma, but is absent in is_associated_with::lung cancer, is_associated_with::prostate cancer, and non-mucinous is_associated_with::ovarian cancer. It is often used in combination with antibodies to CK7 to distinguish different types of glandular tumour.