Cytokeratin 14

Cytokeratin 14 (CK14) is a low molecular weight acidic keratin that is one of the cytoskeletal proteins mainly present in stratified squamous epithelial cells. It has various functions such as maintaining morphology, regulating proliferation, and mediating migration. In clinical practice, CK14 is mainly used as a diagnostic biomarker for squamous cell carcinoma, and it is lowly expressed in adenocarcinoma, which makes it useful for assisting in identification. Moreover, the expression level of CK14 in lung squamous cell carcinoma is positively correlated with tumor invasiveness, speculated that its high expression may stimulate the proliferation and migration of cancer cells. However, some scholars pointed out that CK14 is down-regulated with increased severity of esophageal squamous cell carcinoma and cervical squamous cell carcinoma increases, and its low expression is considered as a pathological feature of malignant transformation of epithelial cells. In addition, the positive rate of CK14 in triple negative breast cancer is significantly increased, which is closely related to the occurrence and development of tumors, which may be because CK14 forms cytoskeleton in cancer cells that can lead to tumor infiltration.