Expression of Keratin in Normal Tissues, Cells, and Tumors

The cytoskeletal proteins in the cytoplasm of epithelial cells mainly include actin, tubulin, and cytokeratins. Cytokeratins are characteristic markers of epithelial cells, forming a large and complex family that is precisely distinguished based on molecular weight using biochemical and immunological methods. The different cytokeratins listed in the table above can be used in clinical practice to mark various epithelial cells, as well as to label tumors originating from and specialized by these epithelial cells, playing a characteristic guiding role in differential diagnosis.